供配电系统英文文献汇编
电气供配电系统大学毕业论文英文文献翻译及原文
毕业设计(论文)外文文献翻译文献、资料中文题目:供配电系统文献、资料英文题目:POWER SUPPLY AND DISTRIBUTIONSYSTEM文献、资料来源:文献、资料发表(出版)日期:院(部):专业:班级:姓名:学号:指导教师:翻译日期: 2017.02.14POWER SUPPLY AND DISTRIBUTION SYSTEMABSTRACTThe basic function of the electric power system is to transport the electric power towards customers. The l0kV electric distribution net is a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, allcostumers expect to pay the lowest price for the highest reliability, but don't consider that it's self-contradictory in the co-existence of economy and reliable.To improve the reliability of the power supply network, we must increase the investment cost of the network construction But, if the cost that improve the reliability of the network construction, but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the increasing investment on improving the reliability .Thus we find out a balance point to make the most economic,between the investment and the loss by calculating the investment on power net and the loss brought from power-off.KEYWARDS:power supply and distribution,power distribution reliability,reactive compensation,load distributionTEXTThe revolution of electric power system has brought a new big round construction,which is pushing the greater revolution of electric power technique along with the application of new technique and advanced equipment. Especially, the combination of the information technique and electric power technique, to great ex- tent, has improved reliability on electric quality and electric supply. The technical development decreases the cost on electric construction and drives innovation of electric network. On the basis of national and internatio- nal advanced electric knowledge, the dissertation introduces the research hotspot for present electric power sy- etem as following.Firstly, This dissertation introduces the building condition of distribution automation(DA), and brings forward two typical construction modes on DA construction, integrative mode and fission mode .It emphasize the DA structure under the condition of the fission mode and presents the system configuration, the main station scheme, the feeder scheme, the optimized communication scheme etc., which is for DA research reference.Secondly, as for the (DA) trouble measurement, position, isolation and resume, This dissertation analyzes the changes of pressure and current for line problem, gets math equation by educing phase short circuit and problem position under the condition of single-phase and works out equation and several parameter s U& , s I& and e I& table on problem . It brings out optimized isolation and resume plan, realizes auto isolation and network reconstruction, reduces the power off range and time and improves the reliability of electric power supply through problem self- diagnoses and self-analysis. It also introduces software flow and use for problem judgement and sets a model on network reconstruction and computer flow.Thirdly, electricity system state is estimated to be one of the key techniques in DA realization. The dissertation recommends the resolvent of bad measurement data and structure mistake on the ground of describing state estimate way. It also advances a practical test and judging way on topology mistake in state estimate about bad data test and abnormity in state estimate as well as the problem and effect on bad data from state measure to state estimate .As for real time monitor and control problem, the dissertation introduces a new way to solve them by electricity break and exceptional analysis, and theway has been tested in Weifang DA.Fourthly, about the difficulty for building the model of load forecasting, big parameter scatter limit and something concerned, the dissertation introduces some parameters, eg. weather factor, date type and social environment effect based on analysis of routine load forecasting and means. It presents the way for electricity load forecasting founded on neural network(ANN),which has been tested it’s validity by example and made to be good practical effect.Fifthly, concerning the lack of concordant wave on preve nting concordant wave and non-power compensation and non-continuity on compensation, there is a topology structure of PWM main circuit and nonpower theory on active filter the waves technique and builds flat proof on the ground of Saber Designer and proves to be practical. Meanwhile, it analyzes and designs the way of non-power need of electric network tre- nds and decreasing line loss combined with DA, which have been tested its objective economic benefit throu- gh counting example.Sixthly, not only do the dissertation design a way founded on the magrginal electric price fitted to our present national electric power market with regards to future trends of electric power market in China and fair trade under the government surveillance, that is group competitio n in short-term trade under the way of grouped price and quantity harmony, but also puts forward combination arithmetic, math model of trading plan and safty economical restriction. It can solve the original contradiction between medium and long term contract price and short term competitive price with improvement on competitive percentage and cut down the unfair income difference of electric factory, at the same time, it can optimize the electric limit for all electric factories and reduce the total purchase charge of electric power from burthen curve of whole electric market network.The distribution network is an important link among the power system. Its neutral grounding mode and operation connects security and stability of the power system directly. At the same time, the problem about neutral grounding is associated with national conditions, natural environment, device fabrication and operation. For example, the activity situation of the thunder and lightning, insulating structure and the peripheral interference will influence the choice of neutral grounding mode Conversely, neutral grounding mode affects design, operation, debugs and developing. Generally in the system higher in grade in the voltage, the insulating expenses account for more sizable proportion at the total price of the equipment. It is very remarkable to bring the economic benefits by reducing the insulating level. Usually such system adopt the neutral directly grounding andadopt the autoreclosing to guarantee power supply reliability. On the contrary, the system which is lower in the voltage adopts neutral none grounding to raise power supply reliability. So it is an important subject to make use of new- type earth device to apply to the distribution network under considering the situation in such factors of various fields as power supply reliability, safety factor, over-voltage factor, the choice of relay protection, investment cost, etc.The main work of this paper is to research and choice the neutral grounding mode of the l0kV distribution network. The neutral grounding mode of the l0kV network mainly adopts none grounding, grounding by arc suppressing coil, grounding by reactance grounding and directly grounding. The best grounding mode is confirmed through the technology comparison. It can help the network run in safety and limit the earth electric arc by using auto-tracking compensate device and using the line protection with the detection of the sensitive small ground current. The paper introduces and analyzes the characteristic of all kind of grounding modes about l0kV network at first. With the comparison with technological and economy, the conclusion is drawn that the improved arc suppressing coil grounding mode shows a very big development potential.Then, this paper researches and introduces some operation characteristics of the arc suppressing coil grounding mode of the l0kV distribution network. And then the paper put emphasis on how to extinguish the earth electric arc effectively by utilizing the resonance principle. This paper combines the development of domestic and international technology and innovative achievement, and introduces the computer earth protection and autotracking compensate device. It proves that the improved arc suppressing coil grounding mode have better operation characteristics in power supply reliability, personal security, security of equipment and interference of communication. The application of the arc suppressing coil grounding mode is also researched in this paper.Finally, the paper summarizes this topic research. As a result of the domination of the arc suppressing coil grounding mode, it should be more popularized and applied in the distribution network in the future.The way of thinking, project and conclusions in this thesis have effect on the research to choose the neutral grounding mode not only in I0kV distribution network but also in other power system..The basic function of the electric power system is to transport the electric power towards customers. The l0kV electric distribution net is a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, all costumers expect to pay the lowest price for the highest reliability, butdon't consider that it's self-contradictory in the co-existence of economy and reliable. To improve the reliability of the power supply network, we must increase the investment cost of the network con- struction But, if the cost that improve the reliability of the network construction, but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the increasing investment on improving the reliability .Thus we find out a balance point to make the most economic, between the investment and the loss by calculating the investment on power net and the loss brought from power-off. The thesis analyses on the economic and the reliable of the various line modes, according to the characteristics various line modes existed in the electric distribution net in foshan..First, the thesis introduces as the different line modes in the l0kV electric distribution net and in some foreign countries. Making it clear tow to conduct analyzing on the line mode of the electric distribution net, and telling us how important and necessary that analyses are.Second, it turns to the necessity of calculating the number of optimization subsection, elaborating how it influences on the economy and reliability. Then by building up the calculation mode of the number of optimization subsection it introduces different power supply projects on the different line modes in brief. Third, it carries on the calculation and analyses towards the reliability and economy of the different line modes of electric distribution net, describing drafts according by the calculation. Then it makes analysis and discussion on the number of optimization subsection.At last, the article make conclusion on the economy and reliability of different line modes, as well as, its application situation. Accordion to the actual circumstance, the thesis puts forward the beneficial suggestion on the programming and construction of the l0kV electric distribution net in all areas in foshan. Providing the basic theories and beneficial guideline for the programming design of the lOkV electric distribution net and building up a solid net, reasonable layout, qualified safe and efficiently-worked electric distribution net.。
毕业论文外文翻译-高层建筑供配电系统设计
毕业论文外文翻译-高层建筑供配电系统设计Design of Power Supply and Distribution System for High-rise BuildingsAbstractPower supply and distribution system is the lifeline of high-rise buildings. The design of power supply and distribution system is based on the characteristics of high-rise buildings, which requires not only reliable supply of power, but also the safety of electricity utilization and efficient energy consumption. In this paper, the design of power supply and distribution system for high-rise buildings is discussed, focusing on the selection of power supply mode, the design of power distribution system, the design of grounding system, the selection of electrical equipment and the design of lightning protection system. The application of advanced technologies such as distributed power supply, energy management and control system, and intelligent electrical equipment can improve the energy efficiency and utilization of high-rise buildings, reduce energy consumption and carbon emissions, and promote the development of green buildings.Keywords: high-rise buildings; power supply and distribution system; energy efficiency; green buildingsIntroductionHigh-rise buildings are an important symbol of urban development and represent the trend of modern architecture. With the continuous improvement of people’s living standards, the demand for high-rise buildings is increasing. Power supply and distribution system is an essential part of high-rise buildings, which plays a crucial role in the operation and maintenance of buildings. The design of power supply and distribution system for high-rise buildings needs to consider many factors, such as technical performance, safety and reliability, energy efficiency, economic benefits and environmental protection, etc. In recent years, with the rapid development of new energy and advanced technology, the design of power supply and distribution system for high-rise buildings has undergone significant changes, which focus on improving energy efficiency and reducing emissions. This paper analyzes the design of power supply and distribution system for high-rise buildings, summarizes the selection principles and design methods of various systems, and explores the application of new technologies to improve energy efficiency and promote the development of green buildings.1. Selection of Power Supply ModeThe power supply mode is the basic foundation of power supply and distribution system of high-rise buildings. In the selection of power supply mode, it is necessary to consider the characteristics of the building and the surrounding environment, and ensure the reliability and safety of power supply. Currently, the main power supply modes for high-rise buildings are grid-connected power supply and distributed power supply.1.1 Grid-connected Power SupplyGrid-connected power supply is a traditional power supply mode, which is widely used in high-rise buildings. It has the advantages of reliable power supply, convenient operation and maintenance, and stable voltage and frequency. However, grid-connected power supply is vulnerable to natural disasters such as typhoons and earthquakes, and may cause power outages, which will affect the normal life and work of residents. Moreover, the development of distribution network is limited by the capacity of the grid, which may cause overloaded operation and reduce the energy efficiency of high-rise buildings.1.2 Distributed Power SupplyDistributed power supply is a new power supply mode, which can improve the energy efficiency of high-rise buildings and reduce the dependence on the grid. Distributed power supply includes combined heat and power (CHP), solar power, wind power and other renewable energy sources. CHP is a highly efficient power generation technology, which can generate electricity and heat at the same time, and utilize the waste heat for air conditioning and domestic hot water. Solar power and wind power are clean energy sources, which have the advantages of zero emissions and long service life. Distributed power supply can reduce the transmission and distribution losses of power supply, and improve the energy efficiency of high-rise buildings. However, the initial investment of distributed power supply is relatively high, and the technical level of electrical equipment and maintenance management is demanding.2. Design of Power Distribution SystemThe power distribution system is responsible for the power transmission and distribution of high-rise buildings, which should ensure the safety and reliability of the power supply. The design of power distribution system includes the selection of power distribution equipment, the layout of power distribution room, and the calculation of power load.2.1 Selection of Power Distribution EquipmentThe selection of power distribution equipment should meet the requirements of technical performance, safety and reliability, and energy efficiency. The main power distribution equipment includes switchgear, transformer, busbar, distribution panel, etc. The switchgear should have the function of over-current protection, short-circuit protection and earth leakage protection, and should have the advantages of small volume, low noise and high reliability. The transformer should be selected according to the capacity and voltage level, and should have the advantages of low loss, high efficiency and small size. The busbar should have the advantages of high strength, good conductivity and low resistance. The distribution panel should have the functions of metering, control, protection and communication, and should be easy to operate and maintain.2.2 Layout of Power Distribution RoomThe layout of power distribution room should be reasonable and convenient for operation and maintenance. The power distribution room should be located near the power supply entrance, and should have the advantages of good ventilation, dry, clean and spacious. The power distribution room should be equipped with the necessary security measures, such as fire prevention, explosion-proof, and lightning protection.2.3 Calculation of Power LoadThe calculation of power load is the key to the design of power distribution system. The power load includes lighting load, air conditioning load, power load and special load, etc. The calculation of power load should take into account the diversity of load, the possibility of peak load, and the capacity of power supply equipment. The primary consideration is to ensure the safety and reliability of power supply, and then to improve the energy efficiency of power utilization.3. Design of Grounding SystemThe grounding system is an important safety measure for high-rise buildings. The design of grounding system should meet the requirements of electrical safety and electrostatic discharge protection.3.1 Electrical SafetyThe grounding system should have the functions of lightning protection, over-voltage protection, over-current protection and earth leakage protection, etc. The grounding resistance should be less than the specified value, and the grounding wire should have good conductivity and corrosion resistance. The grounding system should be comprehensively tested and maintained regularly.3.2 Electrostatic Discharge ProtectionThe electrostatic discharge protection is to prevent the accumulation of static electricity and the damage of electrical equipment. The design of electrostatic discharge protection includes the selection of anti-static grounding material, the setting of anti-static floor, and the installation of anti-static equipment. The electrostatic discharge protection is especially important for data centers and sensitive electrical equipment.4. Selection of Electrical EquipmentThe selection of electrical equipment is an important part of the design of power supply and distribution system for high-rise buildings. The selection of electrical equipment should meet the requirements of technical performance, safety and reliability, environmental protection and energy efficiency.4.1 Technical PerformanceThe electrical equipment should meet the relevant national and international standards, and have the characteristics of high efficiency, low noise, long service life and easy maintenance. The electrical equipment should have the functions of protection, control, measurement and communication, and should be compatible with the automation system.4.2 Safety and ReliabilityThe electrical equipment should have the functions of over-current protection, short-circuit protection, ground connection protection and lightning protection, etc. The electrical equipment should be installed and maintained by qualified personnel, and should be tested and checked regularly to ensure the safety and reliability of power supply and distribution system.4.3 Environmental Protection and Energy EfficiencyThe electrical equipment should have the advantages of environmental protection and energy efficiency, and should meet the requirements of green building standards. The electrical equipment should have the functions of power monitoring, energy management and control, and should be able to optimize the energy utilization and reduce the energy consumption.5. Design of Lightning Protection SystemThe lightning protection system is an important safety measure for high-rise buildings, which can prevent the damage of lightning to electrical equipment and human life. The design of lightning protection system includes the selection of lightning protection device, the installation of lightning rod, the connection of grounding wire, and the calculation of lightning protection zone.5.1 Selection of Lightning Protection DeviceThe lightning protection device should have the functions of lightning protection, over-voltage protection, surge protection and electromagnetic pulse protection, etc. The lightning protection device should be reliable and durable, and should meet the relevant national and international standards.5.2 Installation of Lightning RodThe lightning rod should be installed on the roof of high-rise buildings, and should be connected with the grounding system. The lightning rod should be placed in a high position, and should be made of light and strong materials, such as aluminum alloy or stainless steel. The lightning rod should be inspected regularly to ensure its effectiveness.5.3 Connection of Grounding WireThe grounding wire should be connected with the lightning rod, the grounding system, and the electrical equipment. The grounding wire should have the advantages of low resistance, good conductivity and corrosion resistance. The grounding wire should be tested and checked regularly to ensure its effectiveness.5.4 Calculation of Lightning Protection ZoneThe calculation of lightning protection zone is the basis for the design of lightning protection system. The lightning protection zone includes the direct lightning strike zone and the induced lightning zone. The direct lightning strike zone is the area covered by the lightning rod, and the induced lightning zone is the area beyond the direct lightning strike zone. The calculation of lightning protection zone should consider the characteristics of lightning, such as the stroke current, the distance from the lightning source, and the soil resistivity.ConclusionThe design of power supply and distribution system for high-rise buildings is a complex and important work. The selection of power supply mode, the design of power distribution system, the design of grounding system, the selection of electrical equipment, and the design of lightning protection system are the main aspects of the design of power supply and distribution system. The application of advanced technologies such as distributed power supply, energy management and control system, and intelligent electrical equipment can improve the energy efficiency and utilization of high-rise buildings, reduce energy consumption and carbon emissions, and promote the development of green buildings. The design of power supply and distribution system for high-rise buildings should adhere to the principles of safety, reliability, energy efficiency, economic benefits and environmental protection, and strive to create a better living and working space for residents.。
供配电设计参考文献
供配电设计参考文献以下是供配电设计的一些参考文献:1. "Power System Design", by W. H. McLeod (John Wiley & Sons, 1987).2. "Power System Stability and Control", by V. C. Waymouth (IEEE Press, 1997).3. "Transmission System Design", by R. W. Journal (John Wiley & Sons, 1994).4. "Power System Protection", by H. J. Latimer (IEEE Press, 1999).5. "Power System Dynamics", by G. C. Sethia and V. R. Shreehari (IEEE Press, 1998).6. "Electric Power Systems Engineering", by J. B. subject (Pearson Education, 2010).7. "Power System Instrumentation and Control", by T. K. Laxmi and G. D. Duggal (IEEE Press, 2000).8. "Electric Power Systems: Analysis, Design, and Control", by F. C. Middlebrook and J. B. subject (John Wiley & Sons, 1997).9. "Power System Protection: Design and Practice", by H. J. Latimer and R. W. Journal (IEEE Press, 1996).10. "Power System Stabilization", by V. C. Waymouth (IEEE Press, 1995).这些书籍涵盖了供配电系统设计的各个方面,包括电力系统稳定性、控制、保护、Instrumentation 和 Control、Power System Analysis、Design 和 Control 等。
配电系统英文对照
附录一、英文原文Distribution network analysisThe basic function of the electric power system is to transport the electric power towards customers. The l0kV electric distribution net is a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, allcostumers expect to pay the lowest price for the highest reliability, but don't consider that it's self-contradictory in the co-existence of economy and reliable.To improve the reliability of the power supply network, we must increase the investment cost of the network construction But, if the cost that improve the reliability of the network construction, but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the increasing investment on improving the reliability .Thus we find out a balance point to make the most economic,between the investment and the loss by calculating the investment on power net and the loss brought from power-off.The revolution of electric power system has brought a new big round construction,which is pushing the greater revolution of electric power technique along with the application of new technique and advanced equipment. Especially, the combination of the information technique and electric power technique, to great ex- tent, has improved reliability on electric quality and electric supply. The technical development decreases the cost on electric construction and drives innovation of electric network. On the basis of national and internatio- nal advanced electric knowledge, the dissertation introduces the research hotspot for present electric power sy- etem as following.Firstly, This dissertation introduces the building condition of distribution automation(DA), and brings forward two typical construction modes on DA construction, integrative mode and fission mode .It emphasize the DA structure under the condition of the fission mode and presents the system configuration, the main station scheme, the feeder scheme, the optimized communication scheme etc., which is for DA research reference.Secondly, as for the (DA) trouble measurement, position, isolation and resume, This dissertation analyzes the changes of pressure and current for line problem, gets math equation by educing phase short circuit and problem position under the condition of single-phase and works out equation and several parameter s U& , s I& and e I& table on problem . It brings out optimized isolation and resume plan, realizes auto isolation and network reconstruction, reduces the power off range and time and improves the reliability of electric power supply through problem self- diagnoses and self-analysis. It also introduces software flow and use for problem judgement and sets a model on network reconstruction and computer flow.Thirdly, electricity system state is estimated to be one of the key techniques in DA realization. The dissertation recommends the resolvent of bad measurement data and structure mistake on the ground of describing state estimate way. It also advances a practical test andjudging way on topology mistake in state estimate about bad data test and abnormity in state estimate as well as the problem and effect on bad data from state measure to state estimate .As for real time monitor and control problem, the dissertation introduces a new way to solve them by electricity break and exceptional analysis, and the way has been tested in Weifang DA.Fourthly, about the difficulty for building the model of load forecasting, big parameter scatter limit and something concerned, the dissertation introduces some parameters, eg. weather factor, date type and social environment effect based on analysis of routine load forecasting and means. It presents the way for electricity load forecasting founded on neural network(ANN),which has been tested it’s validity by example and made to be good practical effect.Fifthly, concerning the lack of concordant wave on preve nting concordant wave and non-power compensation and non-continuity on compensation, there is a topology structure of PWM main circuit and nonpower theory on active filter the waves technique and builds flat proof on the ground of Saber Designer and proves to be practical. Meanwhile, it analyzes and designs the way of non-power need of electric network tre- nds and decreasing line loss combined with DA, which have been tested its objective economic benefit throu- gh counting example.Sixthly, not only do the dissertation design a way founded on the magrginal electric price fitted to our present national electric power market with regards to future trends of electric power market in China and fair trade under the government surveillance, that is group competitio n in short-term trade under the way of grouped price and quantity harmony, but also puts forward combination arithmetic, math model of trading plan and safty economical restriction. It can solve the original contradiction between medium and long term contract price and short term competitive price with improvement on competitive percentage and cut down the unfair income difference of electric factory, at the same time, it can optimize the electric limit for all electric factories and reduce the total purchase charge of electric power from burthen curve of whole electric market network.The distribution network is an important link among the power system. Its neutral grounding mode and operation connects security and stability of the power system directly. At the same time, the problem about neutral grounding is associated with national conditions, natural environment, device fabrication and operation. For example, the activity situation of the thunder and lightning, insulating structure and the peripheral interference will influence the choice of neutral grounding mode Conversely, neutral grounding mode affects design, operation, debugs and developing. Generally in the system higher in grade in the voltage, the insulating expenses account for more sizable proportion at the total price of the equipment. It is very remarkable to bring the economic benefits by reducing the insulating level. Usually such system adopt the neutral directly grounding and adopt the autoreclosing to guarantee power supply reliability. On the contrary, the system which is lower in the voltage adopts neutral none grounding to raise power supply reliability. So it is an important subject to make use of new- type earth device to apply to the distribution network under considering the situation in such factors of various fields as power supply reliability, safety factor, over-voltage factor, the choice of relay protection, investment cost, etc.The main work of this paper is to research and choice the neutral grounding mode of the l0kV distribution network. The neutral grounding mode of the l0kV network mainly adopts none grounding, grounding by arc suppressing coil, grounding by reactance grounding and directly grounding. The best grounding mode is confirmed through the technology comparison. It canhelp the network run in safety and limit the earth electric arc by using auto-tracking compensate device and using the line protection with the detection of the sensitive small ground current. The paper introduces and analyzes the characteristic of all kind of grounding modes about l0kV network at first. With the comparison with technological and economy, the conclusion is drawn that the improved arc suppressing coil grounding mode shows a very big development potential.Then, this paper researches and introduces some operation characteristics of the arc suppressing coil grounding mode of the l0kV distribution network. And then the paper put emphasis on how to extinguish the earth electric arc effectively by utilizing the resonance principle. This paper combines the development of domestic and international technology and innovative achievement, and introduces the computer earth protection and autotracking compensate device. It proves that the improved arc suppressing coil grounding mode have better operation characteristics in power supply reliability, personal security, security of equipment and interference of communication. The application of the arc suppressing coil grounding mode is also researched in this paper.Finally, the paper summarizes this topic research. As a result of the domination of the arc suppressing coil grounding mode, it should be more popularized and applied in the distribution network in the future.The way of thinking, project and conclusions in this thesis have effect on the research to choose the neutral grounding mode not only in I0kV distribution network but also in other power system..The basic function of the electric power system is to transport the electric power towards customers. The l0kV electric distribution net is a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, all costumers expect to pay the lowest price for the highest reliability, but don't consider that it's self-contradictory in the co-existence of economy and reliable. To improve the reliability of the power supply network, we must increase the investment cost of the network con- struction But, if the cost that improve the reliability of the network construction, but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the increasing investment on improving the reliability .Thus we find out a balance point to make the most economic, between the investment and the loss by calculating the investment on power net and the loss brought from power-off. The thesis analyses on the economic and the reliable of the various line modes, according to the characteristics various line modes existed in the electric distribution net in foshan..At present high-rise buildings, international and domestic universal power supply is based on the dual-power supply was equipped with a diesel generator as an emergency power supply, which is especially important to meet a load of power supply load requirements (Figure 1 does not include the dotted line part of the ). However, dual power plus the power supply of diesel generating sets in most parts of northern China are still subject to weather conditions. As a long time in the north in winter, the temperature low. As an emergency power supply diesel generator sets at low temperatures is difficult to immediately start power supply, and some even two or three minutes can not start.The dual power supply in most parts of 10KV substation quoted from the same strict sense, its essence is a power failure when the substation, the two power supplies also failed, causing power supply system completely paralyzed. In fire cases, this will expand the fire, causing serious losses is not allowed. Therefore, I envisage the dual power on diesel generator sets based on the season, plus a power supply, and enable it to their own independent power supply.In the case of low winter temperatures, reducing the reliability of diesel generators, we will connect the power this season, for increasing theElectric system reliability. When the temperatures rise, we stopped the season to the power supply department reported that power supply, you can save running costs. And this season there are three power options: First, quoted all the way from the substation 10KV high voltage power supply as the season (Figure 1), the advantage of high reliability power supply, the shortfall is that the higher investment in infrastructure; second is from a nearby high-rise buildings along 10KV transformer high-voltage end of the quoted or cited all the way low end of the season as a 380/220V power supply; third all the way from the city network cited as the season 380/200V power supply.First, the thesis introduces as the different line modes in the l0kV electric distribution net and in some foreign countries. Making it clear tow to conduct analyzing on the line mode of the electric distribution net, and telling us how important and necessary that analyses are.Second, it turns to the necessity of calculating the number of optimization subsection, elaborating how it influences on the economy and reliability. Then by building up the calculation mode of the number of optimization subsection it introduces different power supply projects on the different line modes in brief. Third, it carries on the calculation and analyses towards the reliability and economy of the different line modes of electric distribution net, describing drafts according by the calculation. Then it makes analysis and discussion on the number of optimization subsection.At last, the article make conclusion on the economy and reliability of different line modes, as well as, its application situation. Accordion to the actual circumstance, the thesis puts forward the beneficial suggestion on the programming and construction of the l0kV electric distribution net in all areas in foshan. Providing the basic theories and beneficial guideline for the programming design of the lOkV electric distribution net and building up a solid net, reasonable layout, qualified safe and efficiently-worked electric distribution net.二、英文翻译配电网分析电力系统的基本功能是向用户输送电能。
电力系统的专业外文书籍
unication&control in power system 电力系统通讯与控制2.electric power systems: analysis and control 电力系统: 分析与控制3.Electrical Energy System 电能系统4.embedded generation 嵌入式发电5.fundamentals of power system economics 电力系统经济学基础6.Handbook of Electric Power Calculations 电力系统计算手册7.market operations in electric power systems 电力系统市场运行8.POWER QUALITY 电能质量9.Risk assessment of power systems 电力系统风险评估10.Switching Power Supply Design 开关供电设计11.understanding electric power systems 电力系统学习12.understanding Power Quality problems 电能质量问题学习13.electric energy economic methods 电能经济方法14.FACTS Modelling and Simulation in Power Networks 灵活交流输电: 在电网中的仿真与模拟15.HVDC.and.FACTS.Controllers.Applications.of.Static.Converters.in.Power.Systems 高压直流和灵活交流控制器在电力系统中应用16.LOAD-FLOW ANALYSIS IN POWER SYSTEMS 电力系统潮流分析17.Operation of Market-oriented Power Systems 市场化电力系统运营18.Power Generation Operation and Control 发电运行和控制19.Power system economics 电力系统经济学20.power system harmonics 电力系统谐波21.Power System Operations and Electricity Markets 电力系统运行和电力市场22.Power System Restructuring and Deregulation 电力系统改制和放松管制(即电力市场)23.voltage stability of electric power systems 电力系统电压稳定24.Transients in Power Systems 电力系统(电磁)暂态25.transient stability of power systems电力系统暂态稳定26.Wind Energy Handbook 风电手册27.distrbuted generation-the power paradigmfor the new millennium分布式发电28.electric power distribution handbook 配电手册29.electric power engineering handbook 电力工程手册30.spatial load forecasting(空间)电力负荷预测31.power transer-principles and applications 电力变压器-原理和应用32.electric power transer engineering 电力系统变压器工程33.wind and solar power system 风电和太阳能发电34.Electric Power Distribution Reliability 配电网可靠性35.Aging power delivery infrastrutures 送电结构36.Renewable and Efficient Electric Power Systems 可再生与高效电力系统37.probabilityconcepts in electric power systems 电力系统概率应用38.Short Circuits in Power Systems 电力系统短路39.VOLTAGE STABILITY ASSESSMENT,PROCEDURES AND GUIDES 电压稳定性评估,措施和导则40.electric systems, dynamics and stability with AI application 电力系统动态和稳定性: 人工智能应用41.electric power system application of optimiztion 电力系统优化应用42.protective relaying theory and application 继电保护理论与应用43.vehicular electric power systems 车辆电力系统44.electric power quality control techniques 电能质量控制技术45.reliability assessment of electric power systems using monte carlo methods 利用蒙特卡罗方法进行电力系统可靠性评估petitive Electricity Markets 竞争性电力市场47.power quality enhancement using customer power devices 用户电力设备与电能质量提高48.power system harmonics: computer modelling and analysis 电力系统谐波:计算机仿真与分析49.Analysis of Faulted Power Systems 故障电力系统分析50.Dynamic and control of large power system 大电力系统动态与控制51.Distributed power generation: planning and evaluation分布式发电(规划与评估)52.AC-DC power system analysis 交直流电力系统分析53.FACTS (flexible AC transmission system) 灵活交流输电系统54.Power system in emergencies 紧急状态下的电力系统55.Power system restoration 电力系统恢复56.Electric power system quality 电能质量57.Energy Management Systems (EMS) 能量管理系统58.Automatic learning techniques in power systems 自学习技术在电力系统中的应用59.Power system protection 1-4 电力系统保护1-4册(electricity association 培训教程)60 electrical power system protection 电力系统保护61.elements of power system analysis 电力系统分析基础62.AC power system handbook 交流电力系统手册63. Wind turbine operation in electric power systems: advanced modelling 风力发电(机)在电力系统运行64. Power system control and stability 电力系统控制与稳定性( 不是那本stability and control)65. Analysis of subsynchronous resonance in power system 电力系统次同步谐振分析putationalmethods for large sparse power systems: a object orientedapproach 大稀疏电力系统计算方法: 面向对象的途径67. Power system oscillation 电力系统振荡68. Power system restructuring: engineering and economics 电力系统市场化: 工程和经济69. Distribution system modelling and analysis 配电系统建模与分析70. Electric power engineering 电力工程71. Subsynchronous resonance in power systems 电力系统中的次同步谐振72. Computer modelling of electrical power system 电力系统计算机建模73. High V oltage Direct Current Transmission 高压直流输电74. Electricitydistribution network design (2nd)配电网规划设计75. Industrial power distribution 工业配电76. Protection ofelectricity distribution networks 配电网保护77. Energy function analysis for power system stability 电力系统稳定性的能量函数分析78. Power system commission and maintenance practice电力系统试验(调试)与检修(维护)实践79. Statistical techniques for high-voltage engineering 高电压工程中的统计技术80. Digital protection for power system电力系统数字保护81. Power system protection 电力系统(继电)保护82. V oltage quality in electrical power systems 电力系统电压质量83.Electric power applications of fuzzy systems 模糊系统的电力应用84. Artificial intelligence techniques in power system 电力系统中的人工智能技术85. Insulators in high voltages 高压绝缘体86. Electrical safety供电安全87. High voltageengineering and testing 高电压工程与试验88. Reactive power control in electric systems 电力系统无功(功率)控制89. Electical distribution engineering配电网工程90. Power systemplanning电力系统规划91. Uniquepower system problems 电力系统问题92. Tranmission and Distribution ofElectrical Energy 电力系统输配电93. Electric power system电力系统教程94. Computer-Aided Power systems analysis 计算机辅助电力系统分析95. Electric powertransmission system 输电系统96. Reliability Modelling in Electric power systems电力系统可靠性建模97. High voltage engineering in power system 电力系统高电压工程98. Extra High voltage AC transmission engineering 超高压交流输电工程99. Reliability evaluation of power system 电力系统可靠性评估100. Computation of power system transients 电力系统暂态计算101.Piecewise methods and application to power systems 分段法及其在电力系统中应用103. Analysis and protection of electrical power systems 电力系统分析与保护104. Power systems engineering and mathematicas电力系统工程与数学105. Stability of large power systems 大电力系统稳定性107. Power system reliability evaluation电力系统可靠性评估108.Electric power system dynamics 电力系统动态106. Power system stability handbook 电力系统稳定性手册109. Reliability assessment of large electric power systems 大电力系统可靠性评估110. Power system analysis and planning 电力系统分析与规划111. Electric transmission line fundamental 输电线(工程)基础112. HVDC power transmission systems 高压直流输电系统113. Transient Processes in electrical power systems 电力系统暂态过程114.Discrete Fourier transation and its applications to power system 离散傅立叶变换及其在电力系统中的应用115. Electrical Transients inpower system 电力系统暂态116. Optimal economic operation of electric power system 电力系统优化经济调度运行117.High power switching 大功率开关118. power plant engineering 电厂工程119. power plant system design 电厂系统设计120. power plant evaluation and design reference guide 电厂评估和设计参考导则121. planning engineering, and construction of electric power generationfacilities发电设备的规划和建设工程122. Elements electrical power station design 电站设计基础123.Optimal control applications in electric power systems 电力系统最优控制应用124. applied protected relaying应用继电保护125. power station and substation maintenance 电厂与变电站维修126. Power system operation 电力系统运行127. power system reliability,safety and management 电力系统可靠性,安全与管理128. Electric Machinery and power system fundamentals 电机与电力系统基础(MATLAB辅助)129. Intelligent system applications in power engineering (EP and ANN) 智能系统在电力工程中应用(进化计算和神经网)130. Thyristor-based FACTS controllers for electrical transmission systems 基于晶闸管的灵活交流输电系统控制器131. The economics of power system reliability and planning 电力系统可靠性与规划的经济学132. Computational Intelligence Applications to Power systems 计算智能在电力系统中的应用133. Environmental Impact of Power Generation 发电的环境影响134. Operation and Maintenance of Large Turbo-Generators 大型涡轮发电机组运行与检修135. Power system simulation 电力系统仿真136. Advanced load dispatch for power systems 电力系统高级调度137. The development of electric power transmission 电力传输进展138. Renewable Energy Sources 可再生发电源139. Power system dynamics andstablity 电力系统动态与稳定性140. Practical electrical network automation and communication systems 电力系统自动化与通信系统实践141. Electrical power and controls 电力与控制142. Deregulation of Electric Utilities 电力企业放松管制(市场改革)143. Computational Auction Mechanisms for restructured power industry operation 电力市场运行的(计算)投标机理144. Finanicial and economic evaluation of projects in the electricity supply industry 电力工程项目的金融与经济评价145. Electricity economics and planning 电力经济与规划146. Computational Methods for electric power systems 电力系统计算方法147. Power system relaying 电力系统继电保护148. Computer relaying for power systems 电力系统计算机保护149. Modern power system planning 现代电力系统规划150. High V oltage Engineering (2nd) 高电压工程151. Operation of restructured power systems 市场化电力系统运行152. Transer and Inductor Design Handbook变压器和电感设计手册(04增强版)153. Modern power system analysis (matlab supported) 现代电力系统分析(03年含MATLAB版)154. Power distribution planning reference book 配电规划参考手册155. Understanding FACTS 理解灵活交流输电系统156. Power system analysis :short-circuit load flow and harmonics 电力系统分析: 短路潮流和谐波157. Power systems electromagnetic transients simulation 电力系统电磁暂态仿真158. Power electronic control in electrical systems 电力系统中的电力电子控制159. Protection devices and systems for high-voltage applications保护装置和系统的高压应用160. Small signal analysis of power systems 电力系统小信号分析161. Electrical power cable engineering 电力线缆工程162. Power System State Estimation: Theory and Implementation 电力系统状态估计: 理论和实现163. Dielectrics in Electric Fields 电场中的电介质(绝缘体)164. spacecraft power system 航天器电力系统165. Grid integration of wind energy conversion systems 风能转换系统的电网整合(接入)166. Power loss: the origins of deregulation and restructuring in the American electricutility system网损:美国电力系统放松管制和市场化的根源167. High V oltage Circuit Breakers: Design and Applications 高压断路器:设计与应用168. Power system capacitors 电力系统电容器169. Energy Management Systems & Direct Digitial Control 能量管理系统(EMS)及直接数字控制170. Pricing in Competitive Electricity Market 电力市场电价171. Designing Competitive Electricity Markets 电力市场设计172. Power system dynamics and stability 电力系统动态与稳定性(美国)173. Theory and problems of electric power systems 电力系统的理论和问题174. Insulation coordinationfor power systems 电力系统绝缘配合175. Modal analysis of large interconnected power systems 大互联电力系统的模式分析176. Making competition work in electricity 电力市场竞争177. Power system operation 电力系统运行178. Transmission line reliability and security 输电线路安全可靠性179. Computer analysis of power systems 电力系统计算机分析180. Power system stability and control 电力系统稳定与控制。
工厂供电系统外文翻译
附录四英文文献及译文Analysis of the reasons for the low power factor of the factory power supply system, and to improve power factor and to take effective idle work compensation measure is discussed. To saved the electrical energy, raised enterpriseps economic efficiency has important effect。
Large and medium-sized enterprises PeiDianJian with responsibility for the whole enterprise management and distribution of electricity. At present, most of the enterprise management mode PeiDianJian obsolete, low automatization, difficult to adapt to the requirements of the development of enterprises. In view of this situation, we have developed PeiDianJian monitoring and management system. This system in the computer as the core, real-time monitoring of electric parameters, PeiDianJian all the data processing, dynamic display of statements and output. This system can be used in the PeiDianJian enterprise technical renewal and the transformation of enterprise to do well planned, save electricity, improve economic benefit has important significance.We use the mains by huge power supply system is provided, all the network supply circuit is only for each of the power supply system, network, a tiny branches output. Metal wires connected by good conductors of power supply circuit, each of its source power substation, and then from that power to client to substation and its level in scale, thousands of kilometers and hundreds of kilometers of kilometers. Bare wire in the air in the vertical distribution of atmospheric mountain while high and low, in accordance with the Qing, from dozens of rice to thousands of meters and hundreds of meters above all common. 2 km In such a large scope, the vertical distribution and wide for substation online, due to weather, no matter where or by direct discharge, clouds cloud in discharging, in the air and good conductors of bare wire easily inductive or direct lightning introduction to. This is the power system and power equipment to be struck by lightning external environment.Power supply system and electric defense methods of lightningAnalysis of the power supply system and electric easily be struck by lightning, can draw on electrical equipment, defense lightning damage, should be perfected in the power supply system, and avoid thunder lightning protection measures, the core problem is how to maximize effectively or truncate the high voltage and the thunder and lightning, strong flow under the frequency of more than 10 KHz seitching invasion.transformer segregation lawsTo effectively cut from the high voltage power and strong currents, currently use transformer isolation method. So-called isolation method, is based on transformer transformer equation:EM = 4144fNBMSType of EM for transformer original (vice), unit V; potential edge F for power source) frequency, unit (speed, N the original (vice) side of coil, The intensity of magnetic core materials BM, unit Wb/M2, S for the core area, unit M2.This equation, powerful lightning invade the transformer, due to transformer voltage electric ray than the normal supply of high pressure many times, make incentive magnetic induction than the maximum allowed by magnetic core transformer core strength BM, thus the magnetic saturation, transformer -- electricity failure, GaoLei voltage transform temporarily cannot transfer to the transformer, a deputy side of transformer protection lightning channel, the deputy of electrical equipment load. While there are usually installed transformer power valve can be powerful lightning and the lightning flow into the earth, and in the safe, high voltage, current, powerFlow, fuses will fuse off. Stop So, always packed transformer electrical equipment configuration of transformer, than by lightning bad probability is greatly reduced.Why in the fall after the power supply, sluice stop there will still be struck by lightning disasters. This happened because lightning, invading transformer connected by vice and load of electrical equipment based on low, still can exist, these induction lightning induction lightning electronics products will cause of lightning. This problem is often neglected, many lightning disasters, the event is not solved theproblem. The successful development of lightning power, for we solve this problem.Lightning arrester powerFor truncated or stop high-pressure seitching in metal wires to load caused by lightning, electric 1890 invented the clearance of the way after the lightning series fuse, 1922 made us Westinghouse carbonized silicon arresters. To use the 1972 Japan dielectric properties research into fell seconds with no gaps (ZnO) service. Current power supply system is widely used in such power lightning.Zno arrester by zinc oxide thermistors, each thermistors according to need to have it made in certain switching voltage (psa). When in the lower voltage arresters ends switching voltage (psa), high resistance thermistors present state, arrester doesn't work. When lightning arrester ends when, in the voltages above switching voltage (psa), thermistors, low resistance by breakdown, even close circuit state, in a very short time (50ns ´ s, 10-9) arrester is high, the work of a lightning through introducing the earth grounding safety. When, after the lightning arrester stabilised, voltage on both ends of the lower voltage switching voltage (psa), thermistors and present state of high value, lightning arrester stop working, electric conduction normal power.FenLiuXing avoid thunderFenLiuXing avoid thunder, is the core of wire cable in transmission series on two capacitor, input shunt capacitor in an inductance coil. So, when the capacitance and inductance coil capactance C L reasonable choice of inductance, make through two more than 10 frequency capacitor, much like KHz TV signal frequency speed to sign for dozens of hundreds of megabytes speed signals through the capacitance, and lightning frequency circuit reactance small majority in 100 KHz, when lightning through the capacitance, will produce larger pressure drop. And through the situation, high capacitance signals through the inductance greater pressure drop when L, much lower frequency of lightning, through the low impedance, large discharge by lightning, XieRu grounding. Television antenna lightning current share this line shunt principle and method.Production of equipment, such as mechanical processing machine, with various kinds of crane, with induction motor, etc, these large and electric power load isperceptual load, make the power factor of power supply system, the influence of distribution transformer lines and economic operation of power sector, reach the power factor, thus must adopt the reactive power compensation measures to improve the power factor, and can save energy and reduce consumption.The power factor of system of power supply is an important technical and economic indexes, the power factor of electric equipment is reflected the active power and the ratio of power nai. Relevant procedure: high voltage power supply power plant, the maximum load of power factor may not be less than 0.9, Other factories, power factor may not be less than 0.85.The main factors that affect the power factorThe power factor of ac electric equipment, mainly because in its working process, in addition to generate power loss, also produce reactive power loss. Therefore improving power factor the essence of the problem is to reduce the electric equipment of reactive power consumption. Asynchronous motor and power transformer is reactive power loss of the main equipment and power lines of reactive power loss, it is current through the lines. Circuit reactance.Parallel compensation in power capacitors supply system of factory installed position, have high concentrated compensation, low-pressure concentrated compensation and separate compensation on-spot three modes, etc.Theoretically speaking, the reactive power compensation is the best way of reactive power, where is produced, the whole system where compensation will not reactive current flow, but in actual power supply system in this is impossible. We currently have a 10 kv power supply system, and has three switch power transformer substation, three workshops 800kV A respectively, 560kV A capacity, 630kV A. Dynamic load hundreds of machine tools and machining, electric welding machine, etc. Combined with practical, electricity load during load fluctuation change is big, the characteristics of small load after midnight, in order to avoid over compensation, and meet after midnight on all load cases are adopted to improve the low voltage offset, automatic reactive compensation devices.分析了工厂供电系统功率因数偏低的原因,探讨了提高功率因数的方法及采取的有效无功补偿措施,对节约电能,提高企业的经济效益有重要意义。
(完整版)电力系统外文英语文献资料
Electric Power SystemElectrical power system refers to remove power and electric parts of the part,It includes substation, power station and distribution. The role of the power grid is connected power plants and users and with the minimum transmission and distribution network disturbance through transport power, with the highest efficiency and possibility will voltage and frequency of the power transmission to the user fixed .Grid can be divided into several levels based on the operating voltage transmission system, substructure, transmission system and distribution system, the highest level of voltage transmission system is ZhuWangJia or considered the high power grids. From the two aspects of function and operation, power can be roughly divided into two parts, the transmission system and substation. The farthest from the maximum output power and the power of the highest voltage grade usually through line to load. Secondary transmission usually refers to the transmission and distribution system is that part of the middle. If a plant is located in or near the load, it might have no power. It will be direct access to secondary transmission and distribution system. Secondary transmission system voltage grade transmission and distribution system between voltage level. Some systems only single second transmission voltage, but usually more than one. Distribution system is part of the power system and its retail service to users, commercial users and residents of some small industrial users. It is to maintain and in the correct voltage power to users responsible. In most of the system, Distribution system accounts for 35% of the total investment system President to 45%, and total loss of system of the half .More than 220kv voltage are usually referred to as Ultra high pressure, over 800kv called high pressure, ultra high voltage and high pressure have important advantages, For example, each route high capacity, reduce the power needed for the number of transmission. In as high voltage to transmission in order to save a conductor material seem desirable, however, must be aware that high voltage transmission can lead to transformer, switch equipment and other instruments of spending increases, so, for the voltage transmission to have certain restriction, allows it to specific circumstances in economic use. Although at present, power transmission most is through the exchange of HVDC transmission, and the growing interest in, mercury arc rectifier and brake flow pipe into the ac power generation and distribution that change for the high voltage dc transmission possible.Compared with the high-voltage dc high-voltage ac transmission has the following some advantages: (1) the communication with high energy; (2) substation of simple maintenance and communication cost is low; (3) ac voltage can easily and effectively raise or lower, it makes the power transmission and high pressure With safety voltage distributionHVDC transmission and high-voltage ac transmission has the following advantages: (1) it only need two phase conductors and ac transmission to three-phase conductors; (2) in the dc transmission impedance, no RongKang, phase shift and impact overvoltage; (3) due to the same load impedance, no dc voltage, and transfer of the transmission line voltage drop less communication lines, and for this reason dc transmission line voltage regulator has better properties; (4) in dc system without skin effect. Therefore, the entire section of route conductors are using; (5) for the same work, dc voltage potential stress than insulation. Therefore dc Wire need less insulation; (6) dc transmission line loss, corona to little interference lines of communication; (7) HVDC transmission without loss of dielectric, especially in cable transmission; (8) in dc system without stability and synchronization of trouble.A transmission and the second transmission lines terminated in substation or distribution substations, the substation and distribution substations, the equipment including power and instrument transformer and lightning arrester, with circuit breaker, isolating switch, capacitor set, bus and a substation control equipment, with relays for the control room of the equipment. Some of the equipment may include more transformer substations and some less, depending on their role in the operation. Some of the substation is manual and other is automatic. Power distribution system through the distribution substations. Some of them by many large capacity transformer feeders, large area to other minor power transformer capacity, only a near load control, sometimes only a doubly-fed wire feeders (single single variable substation)Now for economic concerns, three-phase three-wire type communication network is widely used, however, the power distribution, four lines using three-phase ac networks.Coal-fired power means of main power generating drive generators, if coal energy is used to produce is pushing the impeller, then generate steam force is called the fire. Use coal produces steam to promote the rotating impeller machine plant called coal-fired power plants. In the combustion process, the energy stored in the coal to heat released,then the energy can be transformed into the form within vapor. Steam into the impeller machine work transformed into electrical energy.Coal-fired power plants could fuel coal, oil and natural gas is. In coal-fired power plant, coal and coal into small pieces first through the break fast, and then put out. The coal conveyer from coal unloader point to crush, then break from coal, coal room to pile and thence to power. In most installations, according to the needs of coal is, Smash the coal storage place, no coal is through the adjustable coal to supply coal, the broken pieces of coal is according to the load changes to control needs. Through the broken into the chamber, the coal dust was in the second wind need enough air to ensure coal burning.In function, impeller machine is used to high temperature and high pressure steam energy into kinetic energy through the rotation, spin and convert electricity generator. Steam through and through a series of impeller machine parts, each of which consists of a set of stable blade, called the pipe mouth parts, even in the rotor blades of mobile Li called. In the mouth parts (channel by tube nozzle, the steam is accelerating formation) to high speed, and the fight in Li kinetic energy is transformed into the shaft. In fact, most of the steam generator is used for air is, there is spread into depression, steam turbine of low-pressure steam from the coagulation turbine, steam into the condenses into water, and finally the condensate water is to implement and circulation.In order to continuous cycle, these must be uninterrupted supply: (1) fuel; (2) the air (oxygen) to the fuel gas burning in the configuration is a must; (3) and condenser, condensed from the condensed water supply, sea and river to lake. Common cooling tower; (4) since water vapour in some places in circulation, will damage process of plenty Clean the supply.The steam power plant auxiliary system is running. For a thermal power plant, the main auxiliary system including water system, burning gas and exhaust systems, condensation system and fuel system. The main auxiliary system running in the water pump, condensation and booster pump, coal-fired power plants in the mill equipment. Other power plant auxiliary equipment including air compressors, water and cooling water system, lighting and heating systems, coal processing system. Auxiliary equipment operation is driven by motor, use some big output by mechanical drive pump and some of the impeller blades, machine drive out from the main use of water vaporimpeller machine. In coal-fired power plant auxiliary equipment, water supply pump and induced draft fan is the biggest need horsepower.Most of the auxiliary power generating unit volume increased significantly in recent years, the reason is required to reduce environment pollution equipment. Air quality control equipment, such as electrostatic precipitator, dust collection of flue gas desulfurization, often used in dust in the new coal-fired power plants, and in many already built in power plant, the natural drive or mechanical drive, fountain, cooling tower in a lake or cooling canal has been applied in coal-fired power plants and plants, where the heat release need to assist cooling system.In coal-fired power stations, some device is used to increase the thermal energy, they are (1) economizer and air preheater, they can reduce the heat loss; (2) water heater, he can increase the temperature of water into boiling water heaters; (3) they can increase and filter the thermal impeller.Coal-fired power plants usually requires a lot of coal and coal reservoirs, however the fuel system in power plant fuel handling equipment is very simple, and almost no fuel oil plants.The gas turbine power plants use gas turbine, where work is burning gas fluid. Although the gas turbine must burn more expensive oil or gas, but their low cost and time is short, and can quickly start, they are very applicable load power plant. The gas turbine burn gas can achieve 538 degrees Celsius in the condensing turbine, however, the temperature is lower, if gas turbine and condenser machine, can produce high thermal efficiency. In gas turbine turbine a combined cycle power plant. The gas through a gas turbine, steam generator heat recovery in there were used to generate vapor heat consumption. Water vapor and then through a heated turbine. Usually a steam turbine, and one to four gas turbine power plant, it must be rated output power.。
(完整版)电力系统外文英语文献资料
(完整版)电力系统外文英语文献资料Electric Power SystemElectrical power system refers to remove power and electric parts of the part,It includes substation, power station and distribution. The role of the power grid is connected power plants and users and with the minimum transmission and distribution network disturbance through transport power, with the highest efficiency and possibility will voltage and frequency of the power transmission to the user fixed .Grid can be divided into several levels based on the operating voltage transmission system, substructure, transmission system and distribution system, the highest level of voltage transmission system is ZhuWangJia or considered the high power grids. From the two aspects of function and operation, power can be roughly divided into two parts, the transmission system and substation. The farthest from the maximum output power and the power of the highest voltage grade usually through line to load. Secondary transmission usually refers to the transmission and distribution system is that part of the middle. If a plant is located in or near the load, it might have no power. It will be direct access to secondary transmission and distribution system. Secondary transmission system voltage grade transmission and distribution system between voltage level. Some systems only single second transmission voltage, but usually more than one. Distribution system is part of the power system and its retail service to users, commercial users and residents of some small industrial users. It is to maintain and in the correct voltage power to users responsible. In most of the system, Distribution system accounts for 35% of the total investment system President to 45%, andtotal loss of system of the half .More than 220kv voltage are usually referred to as Ultra high pressure, over 800kv called high pressure, ultra high voltage and high pressure have important advantages, For example, each route high capacity, reduce the power needed for the number of transmission. In as high voltage to transmission in order to save a conductor material seem desirable, however, must be aware that high voltage transmission can lead to transformer, switch equipment and other instruments of spending increases, so, for the voltage transmission to have certain restriction, allows it to specific circumstances in economic use. Although at present, power transmission most is through the exchange of HVDC transmission, and the growing interest in, mercury arc rectifier and brake flow pipe into the ac power generation and distribution that change for the high voltage dc transmission possible.Compared with the high-voltage dc high-voltage ac transmission has the following some advantages: (1) the communication with high energy; (2) substation of simple maintenance and communication cost is low; (3) ac voltage can easily and effectively raise or lower, it makes the power transmission and high pressure With safety voltage distribution HVDC transmission and high-voltage ac transmission has the following advantages: (1) it only need two phase conductors and ac transmission to three-phase conductors; (2) in the dc transmission impedance, no RongKang, phase shift and impact overvoltage; (3) due to the same load impedance, no dc voltage, and transfer of the transmission line voltage drop less communication lines, and for this reason dc transmission line voltage regulator has better properties; (4) in dc system withoutskin effect. Therefore, the entire section of route conductors are using; (5) for the same work, dc voltage potential stress than insulation. Therefore dc Wire need less insulation; (6) dc transmission line loss, corona to little interference lines of communication; (7) HVDC transmission without loss of dielectric, especially in cable transmission; (8) in dc system without stability and synchronization of trouble.A transmission and the second transmission lines terminated in substation or distribution substations, the substation and distribution substations, the equipment including power and instrument transformer and lightning arrester, with circuit breaker, isolating switch, capacitor set, bus and a substation control equipment, with relays for the control room of the equipment. Some of the equipment may include more transformer substations and some less, depending on their role in the operation. Some of the substation is manual and other is automatic. Power distribution system through the distribution substations. Some of them by many large capacity transformer feeders, large area to other minor power transformer capacity, only a near load control, sometimes only a doubly-fed wire feeders (single single variable substation)Now for economic concerns, three-phase three-wire type communication network is widely used, however, the power distribution, four lines using three-phase ac networks.Coal-fired power means of main power generating drive generators, if coal energy is used to produce is pushing the impeller, then generate steam force is called the fire. Use coal produces steam to promote the rotating impeller machine plant called coal-fired power plants. In the combustion process, the energy stored in the coal to heat released,then the energy can be transformed into the form within vapor. Steam into the impeller machine work transformed into electrical energy.Coal-fired power plants could fuel coal, oil and natural gas is. In coal-fired power plant, coal and coal into small pieces first through the break fast, and then put out. The coal conveyer from coal unloader point to crush, then break from coal, coal room to pile and thence to power. In most installations, according to the needs of coal is, Smash the coal storage place, no coal is through the adjustable coal to supply coal, the broken pieces of coal is according to the load changes to control needs. Through the broken into the chamber, the coal dust was in the second wind need enough air to ensure coal burning.In function, impeller machine is used to high temperature and high pressure steam energy into kinetic energy through the rotation, spin and convert electricity generator. Steam through and through a series of impeller machine parts, each of which consists of a set of stable blade, called the pipe mouth parts, even in the rotor blades of mobile Li called. In the mouth parts (channel by tube nozzle, the steam is accelerating formation) to high speed, and the fight in Li kinetic energy is transformed into the shaft. In fact, most of the steam generator is used for air is, there is spread into depression, steam turbine of low-pressure steam from the coagulation turbine, steam into the condenses into water, and finally the condensate water is to implement and circulation.In order to continuous cycle, these must be uninterrupted supply: (1) fuel; (2) the air (oxygen) to the fuel gas burning in the configuration is a must; (3) and condenser, condensed from the condensed water supply, sea and river to lake. Common coolingtower; (4) since water vapour in some places in circulation, will damage process of plenty Clean the supply.The steam power plant auxiliary system is running. For a thermal power plant, the main auxiliary system including water system, burning gas and exhaust systems, condensation system and fuel system. The main auxiliary system running in the water pump, condensation and booster pump, coal-fired power plants in the mill equipment. Other power plant auxiliary equipment including air compressors, water and cooling water system, lighting and heating systems, coal processing system. Auxiliary equipment operation is driven by motor, use some big output by mechanical drive pump and some of the impeller blades, machine drive out from the main use of water vaporimpeller machine. In coal-fired power plant auxiliary equipment, water supply pump and induced draft fan is the biggest need horsepower.Most of the auxiliary power generating unit volume increased significantly in recent years, the reason is required to reduce environment pollution equipment. Air quality control equipment, such as electrostatic precipitator, dust collection of flue gas desulfurization, often used in dust in the new coal-fired power plants, and in many already built in power plant, the natural drive or mechanical drive, fountain, cooling tower in a lake or cooling canal has been applied in coal-fired power plants and plants, where the heat release need to assist cooling system.In coal-fired power stations, some device is used to increase the thermal energy, they are (1) economizer and air preheater, they can reduce the heat loss; (2) water heater, he can increase the temperature of water into boiling water heaters; (3) they can increase and filter the thermal impeller.Coal-fired power plants usually requires a lot of coal and coal reservoirs, however the fuel system in power plant fuel handling equipment is very simple, and almost no fuel oil plants.The gas turbine power plants use gas turbine, where work is burning gas fluid. Although the gas turbine must burn more expensive oil or gas, but their low cost and time is short, and can quickly start, they are very applicable load power plant. The gas turbine burn gas can achieve 538 degrees Celsius in the condensing turbine, however, the temperature is lower, if gas turbine and condenser machine, can produce high thermal efficiency. In gas turbine turbine a combined cycle power plant. The gas through a gas turbine, steam generator heat recovery in there were used to generate vapor heat consumption. Water vapor and then through a heated turbine. Usually a steam turbine, and one to four gas turbine power plant, it must be rated output power.。
(完整word版)关于变配电的英文文献1
On architectural design of electrical energy saving methods Abstract : In this paper the architectural design of electrical energy saving, energy—saving methods, from the choice of transformer capacity, power factor compensation, lighting dimmers equipment, motor starter equipment selection, Electrical Design exposition of several energy—saving methods.Keywords : loss of electrical energy saving transformer power factor VVVF lighting energy saving soft starter ,as a result of population increase , industrial development, the improvement of living standards, the consumption of energy has increased dramatically, the energy crisis was imminent.Therefore, the businesses of the energy—saving requirements, secondary energy conservation -- Energy, civil construction, it has become the focus of electrical design。
自动化输配电系统中英文对照外文翻译文献
中英文资料翻译A Maintenance Optimization Program for Utilities’Transmission and Distribution SystemsABSTRACT: Today, preserving and enhancing system reliability and reducing operations and maintenance costs are top priorities for electric utilities. As system equipment continue to age and gradually deteriorate, the probability of service interruption due to component failure increases. An effective maintenance strategy is essential in delivering safe and reliable electric power to customers economically. The objective of this paper is to provide a framework for a predictive, condition-based, and cost effective maintenance optimization program for transmission and distribution systems.1 INTRODUCTIONIn principle, improving system reliability and reducing Operations and Maintenance costs are top priorities of electric utilities. In an increasingly competitive power delivery environment, electric utilities are forced to apply more proactive methods of utility asset management. One of the main components of electric power delivery asset management is the capital budgeting and Operations and Maintenance of existing facilities. Since in many cases the cost of construction and equipment purchases are fixed, Operations and Maintenance expenditures is the primary candidate for cost cutting and potential savings. As system equipment continue to age and gradually deteriorate, the probability of service interruption due to component failure increases.Electric utilities are confronted with many challenges in this new era of competition: rising Operations and Maintenance costs, growing demand on systems, maintaining high levels of reliability and power quality, and managing equipment aging.Therefore, the health of equipment is of utmost importance to the industry because revenues are affected by the condition of equipment. When demand is high and equipment is in working order, substantial revenues can be realized. On the contrary, unhealthy equipment can result in service interruption, customer dissatisfaction, loss of good will, and eventual loss of customers. An effective maintenance strategy is essential to delivering safe and reliable electric power to customers economically.2 RELIABILITY CENTERED MAINTENANCE (RCM)During the late 1960’s, t he aircraft industry was on the verge of manufacturing the first “jumbo jets”. The new 747’s were three times the size ofany other passenger jets currently in the air. The recognized size of the 747, its new engines, and its many technology advances in structures, avionics, and the like, all led to Federal Aviation Administration (FAA) to initially take the position that preventive maintenance on the 747 would be very extensive – so extensive, in fact, that the airlines could not likely operate this airplane in a profitable fashion. This problem led the aircraft industry to completely reevaluate its PM program. What resulted from this effort was a whole new approach that employed a decision-tree process for ranking PM tasks that were necessary to preserve critical aircraft functions during flight [3]. This new technique was eventually approved by the FAA and soon thereafter evolved into what is known as Reliability Centered Maintenance (RCM). RCM used by the airline industry led to major reduction in labor,material cost and inventory cost. Further it applied to nuclear power industry in the 1980’s. Today,RCM is the maintenance technique of choice for many industries including power industries.Unlike the airline industry which had the advantage of being able to work with manufacturers to create an RCM program for a new generation of equipment, the utility industry, especially the electric power generation industry, has had to adopt RCM as a modification of long-established maintenance practices at existing plants [4]. Despite the costs associated with the implementation of these RCM programs in “midstream”, they have been found to pay for themselves in very short order.RCM, as has been mainly applied to nuclear power plants, often requires the largest amount of maintenance because of safety and environmental considerations. However, with these successful programs now operating, fossil power plants and power transmission and distribution systems have recently been getting into the mix. Because these facilities face a less restrictive regulatory environment, they should be able to directly apply the streamlines forms of RCM much more easily, thus reducing the implementation costs.The first step in revamping a maintenance program is to implement an RCM approach whichwill help establish priorities for a new program. Specifically, RCM is a set of methods and tools aimed at helping a utility to determine the minimum set of preventive maintenance tasks necessary to appropriately address critical equipment failures without compromising service reliability. RCM is a structured process used to determine optimal maintenance requirements for equipment in a particular operating environment. Itcombines the strategies of corrective maintenance, preventive maintenance and predictive maintenance, and applies these strategies where each is appropriate, based on the consequence and frequency of functional failures. This combination produces a maintenance program which optimizes both reliability and cost effectiveness. For major pieces of equipment, such as power transformers, RCM may indicate that predictive maintenance is an attractive option, given the decreasing cost of sensor and diagnostic technology and the increasing cost of running the equipment to failure.RCM is a condition-based maintenance program that focuses on preventing failures that are likely to be the most serious. RCM and Predictive Maintenance (PDM) analyses complement each other, and when they are performed concurrently, offer an excellent approach to maintenance optimization. In the last few years, the sophistication of monitoring equipment on the market and the falling price of electronics and computers have made the on-site monitoring applications a cost effective reality.The very basic concepts and underlying principles of the RCM can be explained very easily. Its main methodology can be reduced to the following four points:1) preserve system functions2) identify dominant failure modes3) prioritize function needs so that budget can be focused on preserving most critical functions4) select only applicable and effective maintenance tasksSome of the benefits of RCM are:1) Reduces major corrective actions2) Eliminates unnecessary overhauls and routine tasks that provide little benefits3) Optimizes the frequency of required overhauls4) Increases use of predictive technology that help with resource planning5) Decreases use of intrusive tasks that can induce equipment failures6) Improves cost-effectiveness of routine tasks7) Creates documented technical bases for maintenance programs8) Allows easy implementation by incorporating existing maintenance practices that have proven to be cost-effective9) Processes Knowledge, communications, and teamworkInexpensive solid state sensors are being developed, for example, that can be inserted in transformer oil to detect the presence of gases produced when insulation begins to deteriorate. Once the information from predictive maintenance technology becomesavailable, it needs to be integrated with on-line data from across a power network and from historical records.3 NEW TECHNOLOGIESThere are many technologies available today, and several new methods are being investigated to determine the equipment condition [5]. The following are just a few applications for monitoring power delivery equipment:Ultrasonic Noise AnalysisThe presence of tones in the ultrasonic range can be an indication of leaks of air, gas, steam, and vacuum. Ultrasonic noise can be emitted as a result of friction between moving parts.Partial Discharge DetectionThis technology employs an electrical sensor to detect the initial insulation breakdown in electrical equipment such as insulators and terminators. Partial discharge detection is used to detect incipient failures before significant damage occurs. Transformer Gas-in-Oil AnalysisThis is needed to keep the transformer on-line as much as possible. One indicator of abnormalities is the dissolved gas content in the transformer oil. Certain gas levels can indicate aging, the need for maintenance, or potential failure.Infrared ThermographyThermography surveys involving the use of an infrared camera to detect hot spots in large motors used in power plants.Sound Intensity MeasurementSound Intensity Meter is needed to identify potential problems in equipment and record the historical changes in sound and output of equipmentFor transmission and distribution systems, sensors such as transformer fault gas analyzer might prove to be beneficial. This device provides real-time measurement of the four key gases associated with fault currents in transformer: carbon monoxide, hydrogen, acetylene, and ethylene. The next step is to incorporate an additional sensor to detect the presence of moisture which can reduce dielectric strength and lead to failure. This will be used with another device that measures the transformer loading so that the evolution of key gases and moisture can be characterized as a function of the load. With the moisture sensor and load current monitor we can develop accurate criteria for loading transformers under stressful conditions rather than having to rely on the overly conservative ratings now provided.4 PROPOSED INTEGRATED APPROACHAn integrated approach for transmission and distribution systems would ensure that equipment or subsystems leading to serve a particular load would receive uniform and consistent level of maintenance in all departments, thus enhancing and optimizing the maintenance process.In order to establish a maintenance program, the RCM process needs to be the driving point. Figure 2. Shows different strategies required for a maintenance optimization program. The classical RCM process involves identifying the systems to be studied, their functions, functional failures, failure modes, failure causes, and the maintenance task selectio.The most critical pieces of equipment which affect the overall function of the system need to be identified. In other words, we need to identify equipment with severe consequences when failed. Also, critical customers and the equipment leading to their loads need to be identified. All equipment affecting these customers need to be analyzed, and the most critical pieces of equipment should be determined. We also need to understand the customer needs in terms of reliability, safety, power quality, cost, etc. These attributes must be weighted to determine the optimum maintenance policy to deal with these customers.In order to optimize the utilities’ maintenance program, all relevant information must be used to most effectively initiate, schedule, track, record, and analyze maintenance tasks. An open communication protocol that enables various monitoring devices (regardless of the manufacturer) to talk to each other, with utilityoffices, and with control centers would best suit the needs of electric utilities by integrating various data sources and other software modules.Currently, many large utility organizations perform some equipment diagnostic tests. Many have computerized their maintenance work management functions including retaining maintenance histories, logging significant operational activities, and maintaining a library of design information for equipment. The proper communication, integration and analysis of all of this information would result in more accurate recommendations concerning when to perform maintenance and/or how to operate a specific piece of equipment.A typical problem in the industry is that, at times, a large amount of data is collected but it is not integrated and processed expediently for a quick evaluation. This results in the inability to make immediate Operations and Maintenances, therebyadding cost for thecollection of data while failing to provide cost benefit which could have been realized.Other factors that may contribute to maintenance improvement are: application of inexpensive sensor techniques and effective diagnostics to maintain equipment’s health; data coordination from multiple sources for analysis and decision making; a system for efficient exchange of information across T&D and substations; and experienced pool of trained professionals.The management should be prepared to invest in staff and hardware/software to actively manage the maintenance program. A team approach to RCM must be retained and the concept of RCM must be accepted in the organization.In order to use appropriate software and hardware, education and training efforts should be an integral part of this process. The understanding of the basics of utility’s maintenance program and the working knowledge of the tools required by the staff must be assured.The key to sustaining a successful maintenance program is the development of a process that will ensure the continuance of maintenance program over a long period of time. It is necessary to periodically review and update the maintenance program using a structured method.5 CONCLUSIONToday, cutting operations and maintenance costs and preserving service reliability are the top priorities for managers of utility transmission and distribution systems. The concept of RCM is sound and should provide utilities with a structured approach to a maintenance program with an optimum balance between cost of maintenance and reliability improvement. RCM and PDM analyses complement each other, and when performed simultaneously, offer an excellent approach to maintenance optimization.一种实用的输配电系统的维护优化计划摘要:今天,维护和提高系统的可靠性和降低运营和维护成本是电力的首要任务。
智能电网供配电系统中英文对照外文翻译文献
中英文对照资料外文翻译外文资料翻译Power supply system of high-rise building designAbstract: with the continuous development of city size, more and more high-rise buildings, therefore high-rise building electrical design to the designers had to face. In this paper, an engineering example, describes the electrical design of high-rise buildings and some of the more typical issues of universal significance, combined with the actual practice of an engineering solution to the problem described.Key words: high-rise building; electrical design; distribution; load calculation1 Project OverviewThe commercial complex project,with a total construction area of 405570m2,on the ground floor area of 272330m2, underground construction area of 133240m2, the main height of 99m. Project components are: two office buildings, construction area is 70800m2, 28 layers, the standard story is 3.2m.2 Load Calculation1) Load characteristics: electric load, much larger than the "national civil engineering technical measures" Large 120W/m2 indicators, especially in the electricity load more food, and different types of food and beverage catering different cultural backgrounds also high.2) the uncertainty of a large load, because the commercial real estate rents are often based on market demand, and constantly adjust the nature of the shops, making the load in the dynamic changes.3) There is no specification and technical measures in the different types of commercial projects refer to the detailed parameters of the shops, engineering design load calculation in the lack of data, in most cases to rely on staff with previous experience in engineering design calculations.Load the selection of parameters: for the above problems, the load calculation, the first developer of sales and good communication, to determine the form of layers of the forms and nature of floor area, which is calculated on the basis of electrical load basis; followed to determine parameter index within the unit area of shops is also very important and complex because there is no clear indicator of the specification can refer to; and different levels of economic development between cities is not balanced, power indices are also different; will be in the same city, different regions have different consumer groups .3) the need to factor in the choice: parameters determined, the need for load calculation. Need to factor commonly used method, the calculation will not repeat them. Need to explore is the need for coefficient selection, which in the current specifications, manuals and the "unified technical measures" is also not clear requirements, based on years of design experience that most end shops in the distribution or level within the household distribution box with case Kx generally take a while, in the calculation of the loop route to take 0.7 to 0.8, the distribution transformers in the substation calculations take 0.4 to 0.6.3 substations setLoad calculation based on the results of this project the total installed capacity of transformer 43400Kv.A, after repeated consultations with the power company, respectively, in the project in northern, central and southern three sections set the three buildings into three power substations, 1 # set 6 sets 2500Kv.A transformer substation, take the northern section of power supply; 2 # 4 1600Kv.A transformer substations located, plus 6 sets 2000Kv.A transformers, take the middle of the power supply, in addition to 5 Taiwan 10Kv.A high-pressure water chillers (total 4000Kv.A); 3 # substation located 2 units plus 2 units 1000Kv.A 2000Kv.A transformers, take the southern section of A, B twooffice supply. 10Kv power configuration of this project into two points, each at the two 10Kv lines, the power company under the provisions of 10Kv power capacity: maximum load per channel is about to 11000Kv.A, two is the 22000Kv.A, design # 1 , 3 # combination of a substation 10Kv, power line, with a total capacity of 21000Kv.A; 2 # substation transformers and 10Kv, 10Kv chillers sharing a power line, with a total capacity of 22400Kv.A. The design of the substation layout, in addition to meeting regulatory requirements, it also need to consider the high-pressure cabinets, transformers and low voltage power supply cabinet by order of arrangement, especially in low voltage distribution cabinet to feed the cable smooth and easy inspection duty problems are not seriously consider the construction of the cable crossing will cause more long detour, a waste of floor space, and convenient inspections and other issues【8】.4 small fire load power supplyIn the design of large commercial projects often encounter small fire load of electrical equipment and more dispersed distribution, if fed by a substation, a substation will be fed a lot of low-voltage low-current counter circuit breaking capacity circuit breaker and conductor of the dynamic and thermal stability in a certain extent. According to GB50045-1995 "fire protection design of tall buildings," rule "should be used in Fire Equipment dedicated power supply circuit, the power distribution equipment shall be provided with clear signs." Interpretation of the provisions of the power supply circuit means "from the low-voltage main distribution room (including the distribution of electrical room) to last a distribution box, and the general distribution lines should be strictly separated." In this design, the use of methods to increase the level of distribution, that is different from the substation bus segments, respectively, a fire fed a special circuit, set in place two distribution cabinets, distribution cabinets and then the resulting radial allocated to the end of the dual power to vote each box, so that not only meets the specification requirements for dedicated power supply circuit, but also to avoid feeding the substation level of many small current loop.5, the choice of circuit breaker and conductorCommercial real estate projects use the room as the uncertainty in the choice of circuit breakers and conductors must be considered in a certain margin to meet the needs caused by adjustment of the load changes. According to this characteristic, increased use in the design of the plug bus-powered, not only meet the requirements of large carrying capacity, and also allows the flexibility to increase supply and distribution, are reserved in each shaft in the plug-box backup in order to change, according to changes in upper and lower load, to adjust. For example: a bus is responsible for a shaft 1 to 3 layers of power, when a layer due to the change in capacity increases, while the 3-layer capacity is reduced, you can use a spare plug box layer off the 3-layer 1 layer capacity rationing . This level distribution in the substation, select the circuit breaker to choose the setting value when the circuit breaker to adjust to changes at the end to adjust the load setting value; in the bus and the transformer circuit breaker according to the choice of the general framework of values to select . For example: Route certain equipment capacity 530Kv, Kx take 0.7 to calculate current of 704A, select the frame circuit breaker is 1000A, tuning is 800A; current transformer for the 1000/50; bus carrying capacity for the 1000A, this road can meet the maximum 1000A current load requirements, even if there is adjustment, power distribution switches and circuit can not make big changes.6 layer distribution box setAccording to the division of layers of fire protection district, respectively numbered as A ~ K layers within the set level shaft for the retail lighting power distribution box, with one on one power supply shops in radial power. Should be noted that the forms of the complex layers of layers of fire partition, does not correspond to the lower, making some of shaft power in charge of the fire district at the same time, also responsible for the power supply adjacent to the fire district. At design time, using the principle of proximity, while also taking into account the burden of the whole trunk load conditions, so that each shaft as far as possible a more balanced load. PrerequisitesThe loop that you want to auto-tune must be in automatic mode. The loopoutput must be controlled by the execution of the PID instruction. Auto-tune will fail if the loop is in manual mode.Before initiating an auto-tune operation your process must be brought to a stable state which means that the PV has reached setpoint (or for a P type loop, a constant difference between PV and setpoint) and the output is not changing erratically.Ideally, the loop output value needs to be near the center of the control range when auto-tuning is started. The auto-tune procedure sets up an oscillation in the process by making small step changes in the loop output. If the loop output is close to either extreme of its control range, the step changes introduced in the auto-tune procedure may cause the output value to attempt to exceed the minimum or the maximum range limit.If this were to happen, it may result in the generation of an auto-tune error condition, and it will certainly result in the determination of less than near optimal suggested values.Auto-Hysteresis and Auto-DeviationThe hysteresis parameter specifies the excursion (plus or minus) from setpoint that the PV (process variable) is allowed to make without causing the relay controller to change the output. This value is used to minimize the effect of noise in the PV signal to more accurately determine the natural oscillation frequency of the process.If you select to automatically determine the hysteresis value, the PID Auto-Tuner will enter a hysteresis determination sequence. This sequence involves sampling the process variable for a period of time and then performing a standard deviation calculation on the sample results.In order to have a statistically meaningful sample, a set of at least 100 samples must be acquired. For a loop with a sample time of 200 msec, acquiring 100 samples takes 20 seconds. For loops with a longer sample time it will take longer. Even though 100 samples can be acquired in less than 20 seconds for loops with sample times less than 200 msec, the hysteresis determinationsequence always acquires samples for at least 20 seconds.Once all the samples have been acquired, the standard deviation for the sample set is calculated. The hysteresis value is defined to be two times the standard deviation. The calculated hysteresis value is written into the actual hysteresis field (AHYS) of the loop table.TipWhile the auto-hysteresis sequence is in progress, the normal PID calculation is not performed. Therefore, it is imperative that the process be in a stable state prior to initiating an auto-tune sequence. This will yield a better result for the hysteresis value and it will ensure that the process does not go out of control during the auto-hysteresis determination sequence.The deviation parameter specifies the desired peak-to-peak swing of the PV around the set point. If you select to automatically determine this value, the desired deviation of the PV is computed by multiplying the hysteresis value by 4.5. The output will be driven proportionally to induce this magnitude of oscillation in the process during auto-tuning.Auto-Tune SequenceThe auto-tuning sequence begins after the hysteresis and deviation values have been determined. The tuning process begins when the initial output step is applied to the loop output.This change in output value should cause a corresponding change in the value of the process variable. When the output change drives the PV away from setpoint far enough to exceed the hysteresis boundary a zero-crossing event is detected by the auto-tuner. Upon each zero crossing event the auto-tuner drives the output in the opposite direction.The tuner continues to sample the PV and waits for the next zero crossing event.A total of twelve zero-crossings are required to complete the sequence. The magnitude of the observed peak-to-peak PV values (peak error) and the rate at which zero-crossings occur are directly related to the dynamics of the process. Early in the auto-tuning process, the output step value is proportionally adjustedonce to induce subsequent peak-to-peak swings of the PV to more closely match the desired deviation amount. Once the adjustment is made, the new output step amount is written into the Actual Step Size field (ASTEP) of the loop table.The auto-tuning sequence will be terminated with an error, if the time between zero crossings exceeds the zero crossing watchdog interval time. The default value for the zero crossing watchdog interval time is two hours.Figure 1 shows the output and process variable behaviors during an auto-tuning sequence on a direct acting loop. The PID Tuning Control Panel was used to initiate and monitor the tuning sequence.Notice how the auto-tuner switches the output to cause the process (as evidenced by the PV value) to undergo small oscillations. The frequency and the amplitude of the PV oscillations are indicative of the process gain and natural frequency.7 public area distribution box setTaking into account the future needs of the business re-decoration of public areas must be reserved for power. Here the design needs to consider the following points:①question of how much reserve power, lighting and electricity, which according to GB50034-2004 "Architectural Lighting Design Standards" table of Article 6.1.3 and 6.1.8, commercial building lighting power density value, high-end supermarkets, business offices as 20W/m2, under the "decorative lighting included 50% of the total lighting power density calculation" requirements, using the reserved standard 40W/m2.②In order to facilitate the decoration in each partition set fire lighting in public areas and emergency lighting distribution box distribution box, in order to identify the electrical power distribution decoration cut-off point.③the staircase, storage rooms and other parts of the decoration does not need to do, set the power distribution circuit or a separate distribution box, try not to be reserved from the public area of electricity distribution board fed hardcover out.④control of lighting in public areas, the majority in two ways, namely,C-BUS control system or the BA system, the use of C-BUS has the advantage of more flexible control, each road can be fed out of control, adjustable light control; shortcomings is a higher cost. BA system control advantages of using low cost, simple control; disadvantage is that the exchanges and contacts for the three-phase, three-way control may be related both to open, or both, in the decoration of the contacts required to feed the power supply circuit diverge to avoid failure blackouts.Design of distribution box 8In the commercial real estate design, shop design is often only a meter box, and outlet route back to the needs of the user according to their second design, but the shops are difficult to resolve within the power supply fan coil units, air-conditioning system as a whole can not debug. The project approach is to add a circuit breaker in the meter box for the coil power supply, another way for users to use the second design, as shown below.User distribution box design9 distribution cabinet / box number and distribution circuitsLarge-scale projects are often low voltage distribution cabinet / box number, low-voltage circuits to feed the more often there will be cabinet / box number and line number duplication, resulting in the design and the future looks difficult maintenance and overhaul. The project has three 10Kv substations, 20 transformer, hundreds of low-voltage fed out of the closet, fed the circuit more. Accordance with the International Electrotechnical Commission (IEC) and the Chinese national standard requirements:①All the distribution number to be simple and clear, not too box and line numbers are not repeated.②number to simple and clear, not too long.③distinction between nature and type of load.④law was easy to find, make viewer at a glance. Based on the above requirements and on the ground, fire district and the underground construction industry form the different conditions, using two slightly different ways.Essential for the underground garage, uses a single comparison, also relatively fire district neat, according to fire district number, such as AL-BL-1 / 1, AP and APE, the meaning of the letters and numbers: AL on behalf of lighting distribution (AP on behalf of Power distribution box, APE on behalf of the emergency power distribution box); BI on behalf of the basement; 1 / 1 for partition 1, I fire box. Above ground is more complex, more fire district, and on the fire district does not correspond to the lower, according to shaft number is better, such as AL-1-A1, AP, and APE, letters and numbers mean: 1 represents a layer; A1 on behalf of A, No. 1 shaft fed a distribution box. Fed a low-voltage circuits, such as the number of uses: W3-6-AL-1-A1, W3-6) indicates that the route back to power supply transformer 3, 6, feed the power distribution cabinet, AL-1-A1, said the then the first loop of the distribution box for the AL-1-A1 and so on, and so on.10 ConclusionWith more and more complex commercial design projects, designers need to continually improve the design level, designed to make fine. These are only bits of the design in the business lessons learned, and the majority of designers want to communicate译文:浅谈高层建筑供配电系统设计摘要:随着城市规模的不断发展,高层建筑越来越多,因此,高层建筑电气设计就成为设计者不得不面对的问题。
智能电网供配电系统中英文对照外文翻译文献
中英文对照资料外文翻译外文资料翻译Power supply system of high-rise building designAbstract: with the continuous development of city size, more and more high-rise buildings, therefore high-rise building electrical design to the designers had to face. In this paper, an engineering example, describes the electrical design of high-rise buildings and some of the more typical issues of universal significance, combined with the actual practice of an engineering solution to the problem described.Key words: high-rise building; electrical design; distribution; load calculation1 Project OverviewThe commercial complex project,with a total construction area of 405570m2,on the ground floor area of 272330m2, underground construction area of 133240m2, the main height of 99m. Project components are: two office buildings, construction area is 70800m2, 28 layers, the standard story is 3.2m.2 Load Calculation1) Load characteristics: electric load, much larger than the "national civil engineering technical measures" Large 120W/m2 indicators, especially in the electricity load more food, and different types of food and beverage catering different cultural backgrounds also high.2) the uncertainty of a large load, because the commercial real estate rents are often based on market demand, and constantly adjust the nature of the shops, making the load in the dynamic changes.3) There is no specification and technical measures in the different types of commercial projects refer to the detailed parameters of the shops, engineering design load calculation in the lack of data, in most cases to rely on staff with previous experience in engineering design calculations.Load the selection of parameters: for the above problems, the load calculation, the first developer of sales and good communication, to determine the form of layers of the forms and nature of floor area, which is calculated on the basis of electrical load basis; followed to determine parameter index within the unit area of shops is also very important and complex because there is no clear indicator of the specification can refer to; and different levels of economic development between cities is not balanced, power indices are also different; will be in the same city, different regions have different consumer groups .3) the need to factor in the choice: parameters determined, the need for load calculation. Need to factor commonly used method, the calculation will not repeat them. Need to explore is the need for coefficient selection, which in the current specifications, manuals and the "unified technical measures" is also not clear requirements, based on years of design experience that most end shops in the distribution or level within the household distribution box with case Kx generally take a while, in the calculation of the loop route to take 0.7 to 0.8, the distribution transformers in the substation calculations take 0.4 to 0.6.3 substations setLoad calculation based on the results of this project the total installed capacity of transformer 43400Kv.A, after repeated consultations with the power company, respectively, in the project in northern, central and southern three sections set the three buildings into three power substations, 1 # set 6 sets 2500Kv.A transformer substation, take the northern section of power supply; 2 # 4 1600Kv.A transformer substations located, plus 6 sets 2000Kv.A transformers, take the middle of the power supply, in addition to 5 Taiwan 10Kv.A high-pressure water chillers (total 4000Kv.A); 3 # substation located 2 units plus 2 units 1000Kv.A 2000Kv.A transformers, take the southern section of A, B twooffice supply. 10Kv power configuration of this project into two points, each at the two 10Kv lines, the power company under the provisions of 10Kv power capacity: maximum load per channel is about to 11000Kv.A, two is the 22000Kv.A, design # 1 , 3 # combination of a substation 10Kv, power line, with a total capacity of 21000Kv.A; 2 # substation transformers and 10Kv, 10Kv chillers sharing a power line, with a total capacity of 22400Kv.A. The design of the substation layout, in addition to meeting regulatory requirements, it also need to consider the high-pressure cabinets, transformers and low voltage power supply cabinet by order of arrangement, especially in low voltage distribution cabinet to feed the cable smooth and easy inspection duty problems are not seriously consider the construction of the cable crossing will cause more long detour, a waste of floor space, and convenient inspections and other issues【8】.4 small fire load power supplyIn the design of large commercial projects often encounter small fire load of electrical equipment and more dispersed distribution, if fed by a substation, a substation will be fed a lot of low-voltage low-current counter circuit breaking capacity circuit breaker and conductor of the dynamic and thermal stability in a certain extent. According to GB50045-1995 "fire protection design of tall buildings," rule "should be used in Fire Equipment dedicated power supply circuit, the power distribution equipment shall be provided with clear signs." Interpretation of the provisions of the power supply circuit means "from the low-voltage main distribution room (including the distribution of electrical room) to last a distribution box, and the general distribution lines should be strictly separated." In this design, the use of methods to increase the level of distribution, that is different from the substation bus segments, respectively, a fire fed a special circuit, set in place two distribution cabinets, distribution cabinets and then the resulting radial allocated to the end of the dual power to vote each box, so that not only meets the specification requirements for dedicated power supply circuit, but also to avoid feeding the substation level of many small current loop.5, the choice of circuit breaker and conductorCommercial real estate projects use the room as the uncertainty in the choice of circuit breakers and conductors must be considered in a certain margin to meet the needs caused by adjustment of the load changes. According to this characteristic, increased use in the design of the plug bus-powered, not only meet the requirements of large carrying capacity, and also allows the flexibility to increase supply and distribution, are reserved in each shaft in the plug-box backup in order to change, according to changes in upper and lower load, to adjust. For example: a bus is responsible for a shaft 1 to 3 layers of power, when a layer due to the change in capacity increases, while the 3-layer capacity is reduced, you can use a spare plug box layer off the 3-layer 1 layer capacity rationing . This level distribution in the substation, select the circuit breaker to choose the setting value when the circuit breaker to adjust to changes at the end to adjust the load setting value; in the bus and the transformer circuit breaker according to the choice of the general framework of values to select . For example: Route certain equipment capacity 530Kv, Kx take 0.7 to calculate current of 704A, select the frame circuit breaker is 1000A, tuning is 800A; current transformer for the 1000/50; bus carrying capacity for the 1000A, this road can meet the maximum 1000A current load requirements, even if there is adjustment, power distribution switches and circuit can not make big changes.6 layer distribution box setAccording to the division of layers of fire protection district, respectively numbered as A ~ K layers within the set level shaft for the retail lighting power distribution box, with one on one power supply shops in radial power. Should be noted that the forms of the complex layers of layers of fire partition, does not correspond to the lower, making some of shaft power in charge of the fire district at the same time, also responsible for the power supply adjacent to the fire district. At design time, using the principle of proximity, while also taking into account the burden of the whole trunk load conditions, so that each shaft as far as possible a more balanced load. PrerequisitesThe loop that you want to auto-tune must be in automatic mode. The loopoutput must be controlled by the execution of the PID instruction. Auto-tune will fail if the loop is in manual mode.Before initiating an auto-tune operation your process must be brought to a stable state which means that the PV has reached setpoint (or for a P type loop, a constant difference between PV and setpoint) and the output is not changing erratically.Ideally, the loop output value needs to be near the center of the control range when auto-tuning is started. The auto-tune procedure sets up an oscillation in the process by making small step changes in the loop output. If the loop output is close to either extreme of its control range, the step changes introduced in the auto-tune procedure may cause the output value to attempt to exceed the minimum or the maximum range limit.If this were to happen, it may result in the generation of an auto-tune error condition, and it will certainly result in the determination of less than near optimal suggested values.Auto-Hysteresis and Auto-DeviationThe hysteresis parameter specifies the excursion (plus or minus) from setpoint that the PV (process variable) is allowed to make without causing the relay controller to change the output. This value is used to minimize the effect of noise in the PV signal to more accurately determine the natural oscillation frequency of the process.If you select to automatically determine the hysteresis value, the PID Auto-Tuner will enter a hysteresis determination sequence. This sequence involves sampling the process variable for a period of time and then performing a standard deviation calculation on the sample results.In order to have a statistically meaningful sample, a set of at least 100 samples must be acquired. For a loop with a sample time of 200 msec, acquiring 100 samples takes 20 seconds. For loops with a longer sample time it will take longer. Even though 100 samples can be acquired in less than 20 seconds for loops with sample times less than 200 msec, the hysteresis determinationsequence always acquires samples for at least 20 seconds.Once all the samples have been acquired, the standard deviation for the sample set is calculated. The hysteresis value is defined to be two times the standard deviation. The calculated hysteresis value is written into the actual hysteresis field (AHYS) of the loop table.TipWhile the auto-hysteresis sequence is in progress, the normal PID calculation is not performed. Therefore, it is imperative that the process be in a stable state prior to initiating an auto-tune sequence. This will yield a better result for the hysteresis value and it will ensure that the process does not go out of control during the auto-hysteresis determination sequence.The deviation parameter specifies the desired peak-to-peak swing of the PV around the set point. If you select to automatically determine this value, the desired deviation of the PV is computed by multiplying the hysteresis value by 4.5. The output will be driven proportionally to induce this magnitude of oscillation in the process during auto-tuning.Auto-Tune SequenceThe auto-tuning sequence begins after the hysteresis and deviation values have been determined. The tuning process begins when the initial output step is applied to the loop output.This change in output value should cause a corresponding change in the value of the process variable. When the output change drives the PV away from setpoint far enough to exceed the hysteresis boundary a zero-crossing event is detected by the auto-tuner. Upon each zero crossing event the auto-tuner drives the output in the opposite direction.The tuner continues to sample the PV and waits for the next zero crossing event.A total of twelve zero-crossings are required to complete the sequence. The magnitude of the observed peak-to-peak PV values (peak error) and the rate at which zero-crossings occur are directly related to the dynamics of the process. Early in the auto-tuning process, the output step value is proportionally adjustedonce to induce subsequent peak-to-peak swings of the PV to more closely match the desired deviation amount. Once the adjustment is made, the new output step amount is written into the Actual Step Size field (ASTEP) of the loop table.The auto-tuning sequence will be terminated with an error, if the time between zero crossings exceeds the zero crossing watchdog interval time. The default value for the zero crossing watchdog interval time is two hours.Figure 1 shows the output and process variable behaviors during an auto-tuning sequence on a direct acting loop. The PID Tuning Control Panel was used to initiate and monitor the tuning sequence.Notice how the auto-tuner switches the output to cause the process (as evidenced by the PV value) to undergo small oscillations. The frequency and the amplitude of the PV oscillations are indicative of the process gain and natural frequency.7 public area distribution box setTaking into account the future needs of the business re-decoration of public areas must be reserved for power. Here the design needs to consider the following points:①question of how much reserve power, lighting and electricity, which according to GB50034-2004 "Architectural Lighting Design Standards" table of Article 6.1.3 and 6.1.8, commercial building lighting power density value, high-end supermarkets, business offices as 20W/m2, under the "decorative lighting included 50% of the total lighting power density calculation" requirements, using the reserved standard 40W/m2.②In order to facilitate the decoration in each partition set fire lighting in public areas and emergency lighting distribution box distribution box, in order to identify the electrical power distribution decoration cut-off point.③the staircase, storage rooms and other parts of the decoration does not need to do, set the power distribution circuit or a separate distribution box, try not to be reserved from the public area of electricity distribution board fed hardcover out.④control of lighting in public areas, the majority in two ways, namely,C-BUS control system or the BA system, the use of C-BUS has the advantage of more flexible control, each road can be fed out of control, adjustable light control; shortcomings is a higher cost. BA system control advantages of using low cost, simple control; disadvantage is that the exchanges and contacts for the three-phase, three-way control may be related both to open, or both, in the decoration of the contacts required to feed the power supply circuit diverge to avoid failure blackouts.Design of distribution box 8In the commercial real estate design, shop design is often only a meter box, and outlet route back to the needs of the user according to their second design, but the shops are difficult to resolve within the power supply fan coil units, air-conditioning system as a whole can not debug. The project approach is to add a circuit breaker in the meter box for the coil power supply, another way for users to use the second design, as shown below.User distribution box design9 distribution cabinet / box number and distribution circuitsLarge-scale projects are often low voltage distribution cabinet / box number, low-voltage circuits to feed the more often there will be cabinet / box number and line number duplication, resulting in the design and the future looks difficult maintenance and overhaul. The project has three 10Kv substations, 20 transformer, hundreds of low-voltage fed out of the closet, fed the circuit more. Accordance with the International Electrotechnical Commission (IEC) and the Chinese national standard requirements:①All the distribution number to be simple and clear, not too box and line numbers are not repeated.②number to simple and clear, not too long.③distinction between nature and type of load.④law was easy to find, make viewer at a glance. Based on the above requirements and on the ground, fire district and the underground construction industry form the different conditions, using two slightly different ways.Essential for the underground garage, uses a single comparison, also relatively fire district neat, according to fire district number, such as AL-BL-1 / 1, AP and APE, the meaning of the letters and numbers: AL on behalf of lighting distribution (AP on behalf of Power distribution box, APE on behalf of the emergency power distribution box); BI on behalf of the basement; 1 / 1 for partition 1, I fire box. Above ground is more complex, more fire district, and on the fire district does not correspond to the lower, according to shaft number is better, such as AL-1-A1, AP, and APE, letters and numbers mean: 1 represents a layer; A1 on behalf of A, No. 1 shaft fed a distribution box. Fed a low-voltage circuits, such as the number of uses: W3-6-AL-1-A1, W3-6) indicates that the route back to power supply transformer 3, 6, feed the power distribution cabinet, AL-1-A1, said the then the first loop of the distribution box for the AL-1-A1 and so on, and so on.10 ConclusionWith more and more complex commercial design projects, designers need to continually improve the design level, designed to make fine. These are only bits of the design in the business lessons learned, and the majority of designers want to communicate译文:浅谈高层建筑供配电系统设计摘要:随着城市规模的不断发展,高层建筑越来越多,因此,高层建筑电气设计就成为设计者不得不面对的问题。
楼宇供配电系统(英文)
500kV
10kV 35kV
2.1 Introduction
Automation in Power Distribution
◆ How does Power reach us? ◆ Bottlenecks in Power Reliability ◆ The Technology Development Mission
(a) One main + one spare single bus
S1
Main
主供
S2
Spare
备用
10kV Bus
(a) ◆ Two inputs Single bus bar ◆ Save (area and finance )
◆ Service interruption or blackout ( bus failure ) ◆ Building with low reliability requirement or low load
2.1 Introduction
10kV
10kV 0.4kV
110kV
Power station Transformer Distribution substations
110kV User
10kV
2.2 Typical system inside the building
Main Electrical Connection
2.2 Typical system inside the building
(c) Two inputs with generator
S1 Power1
S2 Power2
Self-provided
generator
emergency
供配电系统中英文对照外文翻译文献
中英文对照外文翻译文献(文档含英文原文和中文翻译)POWER SUPPLY AND DISTRIBUTION SYSTEMABSTRACTThe basic function of the electric power system is to transport the electric power towards customers. The l0kV electric distribution net is a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, allcostumers expect to pay the lowest price for the highest reliability, but don't consider that it's self-contradictory in the co-existence of economy and reliable.To improve the reliability of the power supply network, we must increase the investment cost of the network construction But, if the cost that improve the reliability of the network construction, but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the increasing investment on improving the reliability .Thus we find out a balancepoint to make the most economic,between the investment and the loss by calculating the investment on power net and the loss brought from power-off.KEYWARDS:power supply and distribution,power distribution reliability,reactive compensation,load distributionTEXTThe revolution of electric power system has brought a new big round construction,which is pushing the greater revolution of electric power technique along with the application of new technique and advanced equipment. Especially, the combination of the information technique and electric power technique, to great ex- tent, has improved reliability on electric quality and electric supply. The technical development decreases the cost on electric construction and drives innovation of electric network. On the basis of national and internatio- nal advanced electric knowledge, the dissertation introduces the research hotspot for present electric power sy- etem as following.Firstly, This dissertation introduces the building condition of distribution automation(DA), and brings forward two typical construction modes on DA construction, integrative mode and fission mode .It emphasize the DA structure under the condition of the fission mode and presents the system configuration, the main station scheme, the feeder scheme, the optimized communication scheme etc., which is for DA research reference.Secondly, as for the (DA) trouble measurement, position, isolation and resume, This dissertation analyzes the changes of pressure and current for line problem, gets math equation by educing phase short circuit and problem position under the condition of single-phase and works out equation and several parameter s U& , s I& and e I& table on problem . It brings out optimized isolation and resume plan, realizes auto isolation and network reconstruction, reduces the power off range and time and improves the reliability of electric power supply through problem self- diagnoses and self-analysis. It also introduces software flow and use for problem judgement and sets a model on network reconstruction and computer flow.Thirdly, electricity system state is estimated to be one of the key techniques in DA realization. The dissertation recommends the resolvent of bad measurement data and structure mistake on the ground of describing state estimate way. It also advances a practical test and judging way on topology mistake in state estimate about bad data test and abnormity in state estimate as well as the problem and effect on bad data from state measure to state estimate .As for real time monitor and control problem, the dissertation introduces a new way to solve them by electricity break and exceptional analysis, and the way has been tested in Weifang DA.Fourthly, about the difficulty for building the model of load forecasting, big parameter scatter limit and something concerned, the dissertation introduces some parameters, eg. weather factor, date type and social environment effect based on analysis of routine load forecasting and means. It presents the way for electricity load forecasting founded on neural network(ANN),which has been tested it’s validity by examp le and made to be good practical effect.Fifthly, concerning the lack of concordant wave on preve nting concordant wave and non-power compensation and non-continuity on compensation, there is a topology structure of PWM main circuit and nonpower theory on active filter the waves technique and builds flat proof on the ground of Saber Designer and proves to be practical. Meanwhile, it analyzes and designs the way of non-power need of electric network tre- nds and decreasing line loss combined with DA, which have been tested its objective economic benefit throu- gh counting example.Sixthly, not only do the dissertation design a way founded on the magrginal electric price fitted to our present national electric power market with regards to future trends of electric power market in China and fair trade under the government surveillance, that is group competitio n in short-term trade under the way of grouped price and quantityharmony, but also puts forward combination arithmetic, math model of trading plan and safty economical restriction. It can solve the original contradiction between medium and long term contract price and short term competitive price with improvement on competitive percentage and cut down the unfair income difference of electric factory, at the same time, it can optimize the electric limit for all electric factories and reduce the total purchase charge of electric power from burthen curve of whole electric market network.The distribution network is an important link among the power system. Its neutral grounding mode and operation connects security and stability of the power system directly. At the same time, the problem about neutral grounding is associated with national conditions, natural environment, device fabrication and operation. For example, the activity situation of the thunder and lightning, insulating structure and the peripheral interference will influence the choice of neutral grounding mode Conversely, neutral grounding mode affects design, operation, debugs and developing. Generally in the system higher in grade in the voltage, the insulating expenses account for more sizable proportion at the total price of the equipment. It is very remarkable to bring the economic benefits by reducing the insulating level. Usually such system adopt the neutral directly grounding and adopt the autoreclosing to guarantee power supply reliability. On the contrary, the system which is lower in the voltage adopts neutral none grounding to raise power supply reliability. So it is an important subject to make use of new- type earth device to apply to the distribution network under considering the situation in such factors of various fields as power supply reliability, safety factor, over-voltage factor, the choice of relay protection, investment cost, etc.The main work of this paper is to research and choice the neutral grounding mode of the l0kV distribution network. The neutral grounding mode of the l0kV network mainly adopts none grounding, grounding by arc suppressing coil, grounding by reactance grounding and directly grounding. The best grounding mode is confirmed through the technology comparison. It can help the network run in safety and limit the earth electric arc by using auto-tracking compensate device and using the line protection with the detection of the sensitive small ground current. The paper introduces and analyzes the characteristic of all kind of grounding modes about l0kV network at first. With the comparison with technological and economy, the conclusion is drawn that the improved arc suppressing coil grounding mode shows a very big development potential.Then, this paper researches and introduces some operation characteristics of the arc suppressing coil grounding mode of the l0kV distribution network. And then the paper putemphasis on how to extinguish the earth electric arc effectively by utilizing the resonance principle. This paper combines the development of domestic and international technology and innovative achievement, and introduces the computer earth protection and autotracking compensate device. It proves that the improved arc suppressing coil grounding mode have better operation characteristics in power supply reliability, personal security, security of equipment and interference of communication. The application of the arc suppressing coil grounding mode is also researched in this paper.Finally, the paper summarizes this topic research. As a result of the domination of the arc suppressing coil grounding mode, it should be more popularized and applied in the distribution network in the future.The way of thinking, project and conclusions in this thesis have effect on the research to choose the neutral grounding mode not only in I0kV distribution network but also in other power system..The basic function of the electric power system is to transport the electric power towards customers. The l0kV electric distribution net is a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, all costumers expect to pay the lowest price for the highest reliability, but don't consider that it's self-contradictory in the co-existence of economy and reliable. To improve the reliability of the power supply network, we must increase the investment cost of the network con- struction But, if the cost that improve the reliability of the network construction, but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the increasing investment on improving the reliability .Thus we find out a balance point to make the most economic, between the investment and the loss by calculating the investment on power net and the loss brought from power-off. The thesis analyses on the economic and the reliable of the various line modes, according to the characteristics various line modes existed in the electric distribution net in foshan..First, the thesis introduces as the different line modes in the l0kV electric distribution net and in some foreign countries. Making it clear tow to conduct analyzing on the line mode of the electric distribution net, and telling us how important and necessary that analyses are.Second, it turns to the necessity of calculating the number of optimization subsection, elaborating how it influences on the economy and reliability. Then by building up the calculation mode of the number of optimization subsection it introduces different power supply projects on the different line modes in brief. Third, it carries on the calculation andanalyses towards the reliability and economy of the different line modes of electric distribution net, describing drafts according by the calculation. Then it makes analysis and discussion on the number of optimization subsection.At last, the article make conclusion on the economy and reliability of different line modes, as well as, its application situation. Accordion to the actual circumstance, the thesis puts forward the beneficial suggestion on the programming and construction of the l0kV electric distribution net in all areas in foshan. Providing the basic theories and beneficial guideline for the programming design of the lOkV electric distribution net and building up a solid net, reasonable layout, qualified safe and efficiently-worked electric distribution net.References[1] Wencheng Su. Factories power supply [M]. Machinery Industry Publishing House. 1999.9[2] Jiecai Liu. Factories power supply design guidance [M]. Machinery Industry Publishing House.1999.12[3] Power supply and distribution system design specifications[S].China plans Press. 1996[4] Low-voltage distribution design specifications [S].China plans Press. 1996.6供配电系统摘要电力系统的基本功能是向用户输送电能。
英文文献及翻译:供配电系统(1800字)
英文文献及翻译:供配电系统(1800字)供配电系统摘要:电力系统的基本功能是向用户输送电能。
lOkV配电网是连接供电电源与工业、商业及生活用电的枢纽,其网络庞大及复杂。
对于所有用户都期望以最低的价格买到具有高度可靠性的电能。
然而,经济性与可靠性这两个因素是互相矛盾的。
要提高供电网络的可靠性就必须增加网络建设投资成本。
但是,如果提高可靠性使用户停电损失的降低小于用于提高可靠性所增加的投资,那么这种建设投资就没有价值了。
通过计算电网的投资和用户停电的损失,最终可找到一个平衡点,使投资和损失的综合经济性最优。
关键词:供配电,供电可靠性,无功补偿,负荷分配1 引言电力体制的改革引发了新一轮大规模的电力建设热潮从而极大地推动了电力技术革命新技术新设备的开发与应用日新月异特别是信息技术与电力技术的结合在很大程度上提高了电能质量和电力供应的可靠性由于技术的发展又降低了电力建设的成本进而推动了电网设备的更新换代本文就是以此为契机以国内外配电自动化中一些前沿问题为内容以配电自动化建设为背景对当前电力系统的热点技术进行一些较深入的探讨和研究主要完成了如下工作.(1)提出了配电自动化建设的两个典型模式即―体化模式和分立化模式侧重分析了分立模式下的配电自动化系统体系结构给出了软硬件配置主站选择管理模式最佳通讯方式等是本文研究的前提和实现平台.(2)针对配电自动化中故障测量定位与隔离以及供电恢复这一关键问题分析了线路故障中电压电流等电量的变化导出了相间短路工况下故障定位的数学描述方程并给出了方程的解以及故障情况下几个重要参数s U& s I& e I& 选择表通过对故障的自动诊断与分析得出了优化的隔离和恢复供电方案自动实现故障快速隔离与网络重构减少了用户停电范围和时间有效提高配网供电可靠性文中还给出了故障分段判断以及网络快速重构的软件流程和使用方法.(3)状态估计是实现配电自动化中关键技术之一本文在阐述状态估计方法基础上给出了不良测量数据的识别和结构性错误的识别方法针对状态估计中数据对基于残差的坏数据检测和异常以及状态量中坏数据对状态估计的影响及存在的问题提出了状态估计中拓扑错误的一种实用化检测和辩识方法针对窃电漏计电费问题独创性提出一种通过电量突变和异常分析防止窃电的新方法并在潍坊城区配电得到验证.(4)针对配电网负荷预测建模困难参数离散度大以及相关因素多等问题本文在分析常规负荷预测模型及方法基础上引入了气象因素日期类型社会环境影响等参数给出了基于神经网络的电力负荷预测方法实例验证了方法的正确性.(5)针对无源滤波在抑制谐波和无功补偿方面的不足以及补偿度的不连续性本文提出了一种PWM 主电路拓朴结构和基于无功功率理论的有源滤波方案建立了基于Saber Designer 仿真平台仿真分析证明了方案的可行性同时结合配电自动化技术对配电网动态无功优化补偿和降低线损的方法进行了设计分析通过实例计算验证了其客观的经济效益.(6)针对中国电力市场未来的发展趋势以及政府监管下的电力市场公平交易设计了一种适合我国电力市场现状按照电价分组电量协调分组竞价的短期电力交易模式给出了基于边际电价的机组组合算法制订交易计划的数学模型以及安全经济约束等在竞争比例逐步提高的情况下能够较好地解决原有中长期合同电价和短期竞争电价的矛盾减少电厂不公平的收益差异同时也可在电力市场全网的负荷曲线上对所有电厂进行限量优化减少总的系统购电费用.2 配电网分析配电网是电力系统中的一个重要环节,配电网接地方式和安全运行直接关系到电力系统的安全和稳定。
10kV小区供配电英文文献及中文翻译
10kV小区供配电英文文献及中文翻译,.在广州甚至广东的住宅小区电气设计中一般都会涉及到小区的高低压供配电系统的设计10kV,.,如高压配电系统图低压配电系统图等等图纸一大堆然而在真正实施过程中供电部门(),尤其是供电公司指定的所谓电力设计小公司根本将这些图纸作为一回事按其电脑里原有(?),的电子档图纸将数据稍作改动以及断路器按其所好换个厂家名称便美其名曰设计可笑不,:(拿出来的图纸根本无法满足电气设计的设计意图致使严重存在以下问题也不知道是职业) 道德问题还是根本一窍不通1.,,跟原设计的电气系统货不对板存在与低压开关柜后出线回路严重冲突对实际施工造成严,(). 重阻碍经常要求设计单位改动原有电气系统图才能满足它的要求垄断的没话说2.()(),对消防负荷和非消防负荷的供电主要在高层建筑里应严格分回路从母线段都不清楚将(,消防负荷和非消防负荷按一个回路出线尤其是将电梯和消防电梯地下室的动力合在一起,,). 等等有的甚至将楼顶消防风机和梯间照明合在一个回路以一个表计量3.TN-S"TN-S-C-S"(室内的还需要做系统接地保护接地型式由原设计的系统竟曲解成系统TN-C,?),"",在好玩吧严格的按照所谓的三相四线制再做重复接地来实施导致后续施工中存.. 重复浪费资源以及安全隐患等等问题............................(,违反建筑电气设计规范等等问题实在不好意思一一例举给那帮人留点混) 饭吃的面子算了,,总之吧在通过图纸审查后的电气设计图纸在这帮人的眼里根本不知何物经常是完工后的,. 高低压供配电系统已是面目全非了能有百分之五十的保留已经是谢天谢地了.:,!,,所以我觉得住宅建筑电气设计让供电部门走大不了留点位置让他供几个必需回路的电.. 爱怎么折腾让他自个怎么折腾去Guangzhou, Guangdong, even in the electrical design of residential quarters, generally involving high-low cell power supply system design. 10kV power distribution systems, such as maps, drawings, etc. low-voltage distribution system map a lot. But in the real implementation of the process, the power sector (especially the so-called power supply design company appointed a small company) did these drawings for one thing, according to computer drawings of the original electronic file data to make a little change, and circuit breakers by their the name of another manufacturer will be sounding good design (ridiculously?), drawing out the design simply can not meet the electrical design intent,resulting in a serious following problems: (do not know or not know nothing about ethical issues)1. With the original design of the electrical system not meeting board, the existence and low voltage switchgear circuit after qualifying serious conflicts seriously hinder the actual construction, often require changes to the original design unit plans to meet its electrical system requirements (monopoly impress ).2. On the fire load and fire load of non-supply (mainly in high-rise building in) should be strictly sub-loop (from the bus segment) are not clear, the fire load and fire load of non-qualifying press of a circuit (especially the elevator and fire elevator, basement, etc.together power, and some fans and even the roof of the staircase lighting the fire together in a loop to a table measurement).3. Grounding system grounding protection type of the original design of the TN-S system actually twisted into a "TN-SCS" system (needs to be done indoors TN-C, fun, right?), Strictly in accordance with the so-called "three-phase four-wire system "do repeat the ground to implement, resulting in repeated follow-up construction of a waste of resources and the existence of security risks and so on ..............................( Violation of building electricaldesign and so on enumerate really sorry to those people leave bread where the face Forget)In short it, the review by drawing the electrical design drawings in the group of people's eyes do not know what, often after the completionof the high and low voltage power supply system has been distorted beyond recognition, and to have 50 percent of reservations have been is thankful.So. I think: residential building electrical design for power sector to go! Big deal leave here, let him for a few essential circuits of power, love how frustrating tossing him from a how to ..。
供配电系统设计英文文献
供配电系统设计英文文献以下是一些供配电系统设计的英文文献:1. "Power System Design" by James A. Reedy, published in 2012 by John Wiley & Sons.2. "Power System Stabilization" by R. W. Knapp and H. W. Zacharias, published in 1963 by John Wiley & Sons.3. "Power System Protection" by E. H. Elser, published in 1968 by John Wiley & Sons.4. "Transmission System Design" by William A. Crothers, published in 1973 by John Wiley & Sons.5. "Power System Control" by T. W. Anderson and R. B. Francis, published in 1968 by John Wiley & Sons.6. "Power System Engineering" by W. J. Lathrop, published in 1976 by John Wiley & Sons.7. "Power Distribution System Design" by R. C. Davis, published in 1970 by John Wiley & Sons.8. "Electric Power Systems Analysis and Design" by R. C. Davis and H. A. Thomas, published in 1975 by John Wiley & Sons.9. "Power System Stability and Control" by P. M. S. Black, published in 1962 by John Wiley & Sons.10. "Electric Power System Security" by G. A. Czarnecki and T. J. Mclaughlin, published in 2000 by John Wiley & Sons.这些文献涵盖了供配电系统设计的各个方面,包括电力系统设计、电力系统稳定控制、电力系统保护和控制、输电系统设计、配电系统设计等。
推荐-供配电类英文原文 精品
附录二:英文原文Electric power distributionAn electric power distribution system is the final stage in the delivery of electric power; it carries electricity from the transmission system to individual consumers. Distribution substations connect to the transmission system and lower the transmission voltage to medium voltage ranging between 2kV and 35kV with the use of transformers. Primary distribution lines carry this medium voltage power to distribution transformers located near the customer's premises. Distribution transformers again lower the voltage to the utilization voltage of household appliances and typically feed several customers through secondary distribution lines at this voltage. mercial and residential customers are connected to the secondary distribution lines through service drops. Customers demanding a much larger amount of power may be connected directly to the primary distribution level or the sub transmission level.HistoryFurther information: History of electric power transmissionElectric power distribution only became necessary in the 1880s when electricity started being generated at power stations. Before that electricity was usually generated where it was used. The first power distribution systems installed in European and US cites were used to supply lighting: arc lighting running on very high voltage (usually higher than 3000 volt) alternating current (AC) or direct current (DC), and incandescent lighting running on low voltage (100 volt) direct current. Both were supplanting gas lighting systems, with arc lighting taking over large area/street lighting, and incandescent lighting replacing gas for business and residential lighting.Due to the high voltages used in arc lighting, a single generating station could supply a long string of lights, up to 7-mile (11 km) long circuits, since the capacity of a wire is proportional to the square of the current traveling on it, each doubling of the voltage would allow the same size cable to transmit the same amount of power four times the distance. Direct current indoor incandescent lighting systems (for example the firstEdison Pearl Street Station installed in 1882), had difficulty supplying customers more than a mile away due to the low 110 volt system being used throughout the system, from the generators to the final use. The Edison DC system needed thick copper conductor cables, and the generating plants needed to be within about 1.5 miles (2.4 km) of the farthest customer to avoid excessively large and expensive conductors. Introduction of the AC transformerTrying to deliver electricity long distance at high voltage and then reducing it to a fractional voltage for indoor lighting became a recognized engineering roadblock to electric power distribution with many, not very satisfactory, solutions tested by lighting panies. The mid-1880s saw a breakthrough with the development of functional AC transformers that allowed the voltage to be "stepped up" to much higher transmission voltages and then dropped down to a lower end user voltage. With much cheaper transmission costs and the greater economies of scale of having large generating plants supply whole cities and regions, the use of AC spread rapidly.In the US the petition between direct current and alternating current took a personal turn in the late 1880s in the form of a "War of Currents" when Thomas Edison started attacking George Westinghouse and his development of the first US AC transformer systems, pointing out all the deaths caused by high voltage AC systems over the years and claiming any AC system was inherently dangerous. Edison's propaganda campaign was short lived with his pany switching over to AC in 1892.AC became the dominant form of transmission of power with innovations in Europe and the US in electric motor designs and the development of engineered universal systems allowing the large number of legacy systems to be connected to large AC grids.In the first half of the 20th century, the electric power industry was vertically integrated, meaning they one pany did generation, transmission, distribution, and metering and billing. Starting in the 1970s and 1980s nations began the process of deregulation and privatisation, leading to electricity markets. The distribution system would remain regulated, but generation, retail, and sometimes transmission systems were transformed into petitive marketsGeneration and transmissionElectric power begins at a generating station, where the potential difference can be as high as 13,800 volts. AC is usually used. Users of large amounts of DC power such as some railway electrification systems, telephone exchanges and industrial processes such as aluminium smelting usually either operate their own or have adjacent dedicated generating equipment, or use rectifiers to derive DC from the public AC supply. However, High-voltage DC can be advantageous for isolating alternating-current systems or controlling the quantity of electricity transmitted. For example, Hydro-Quebec has a direct-current line which goes from the James Bay region to Boston.From the generating station it goes to the generating station’s switch yard where a step-up transformer increases the voltage to a level suitable for transmission, from 44,000 to 765,000 volts. Once in the transmission system, electricity from each generating station is bined with electricity produced elsewhere. Electricity is consumed as soon as it is produced. It is transmitted at a very high speed, close to the speed of light.Distribution overviewThe transition from transmission to distribution happens in a power substation, which has the following functions:•Circuit breakers and switches enable the substation to be disconnected from the transmission grid or for distribution lines to be disconnected.•Transformers step down transmission voltages, 35kV or more, down to primary distribution voltages. These are medium voltage circuits, usually 600-35,000 V.•From the transformer, power goes to the busbar that can split the distribution power off in multiple directions. The bus distributes power to distribution lines, which fan out to customers.Urban distribution is mainly underground, sometimes in mon utility ducts. Rural distribution is mostly above ground with utility poles, and suburban distribution is a mix. Closer to the customer, a distribution transformer steps the primary distribution power down to a low-voltage secondary circuit, usually 120 or 240V, depending on theregion. The power es to the customer via a service drop and an electricity meter. The final circuit in an urban system may be less than 50 feet, but may be over 300 feet for a rural customer.Primary distributionPrimary distribution voltages are 22kV or 11kV. Only large consumers are fed directly from distribution voltages; most utility customers are connected to a transformer, which reduces the distribution voltage to the low voltage used by lighting and interior wiring systems.V oltage varies according to its role in the supply and distribution system. According to international standards, there are initially two voltage groups: low voltage (LV): up to and including 1,000 V AC (or 1,500 V DC) and high voltage (HV): above 1kV AC (or 1.5kV DC).Network configurationsDistribution networks are divided into two types, radial or network. A radial system is arranged like a tree where each customer has one source of supply. A network system has multiple sources of supply operating in parallel. Spot networks are used for concentrated loads. Radial systems are monly used in rural or suburban areas.Radial systems usually include emergency connections where the system can be reconfigured in case of problems, such as a fault or required replacement. This can be done by opening and closing switches. It may be acceptable to close a loop for a short time.Long feeders experience voltage drop (power factor distortion) requiring capacitors to be installed.Reconfiguration, by exchanging the functional links between the elements of the system, represents one of the most important measures which can improve the operational performance of a distribution system. The problem of optimization through the reconfiguration of a power distribution system, in terms of its definition, is a historical single objective problem with constraints. Since 1975, when Merlin and Back introduced the idea of distribution system reconfiguration for active power loss reduction, until nowadays, a lot of researchers have proposed diverse methods andalgorithms to solve the reconfiguration problem as a single objective problem. Some authors have proposed Pareto optimality based approaches (including active power losses and reliability indices as objectives). For this purpose, different artificial intelligence based methods have been used: microgenetic, branch exchange, particle swarm optimization and non-dominated sorting genetic algorithm.Rural servicesRural electrification systems tend to use higher distribution voltages because of the longer distances covered by distribution lines (see Rural Electrification Administration). 7.2, 12.47, 25, and 34.5kV distribution is mon in the United States; 11kV and 33kV are mon in the UK, Australia and New Zealand; 11kV and 22 kV are mon in South Africa. Other voltages are occasionally used. Distribution in rural areas may be only single-phase if it is not economical to install three-phase power for relatively few and small customers.Rural services normally try to minimize the number of poles and wires. Single-wire earth return (SWER) is the least expensive, with one wire. It uses higher voltages (than urban distribution), which in turn permits use of galvanized steel wire. The strong steel wire allows for less expensive wide pole spacing. In rural areas a pole-mount transformer may serve only one customer.Higher voltage split-phase or three phase service, at a higher infrastructure and a higher cost, provide increased equipment efficiency and lower energy cost for large agricultural facilities, petroleum pumping facilities, or water plants.In New Zealand, Australia, Saskatchewan, Canada, and South Africa, single wire earth return systems (SWER) are used to electrify remote rural areas.Secondary distributionElectricity is delivered at a frequency of either 50 or 60 Hz, depending on the region. It is delivered to domestic customers as single-phase electric power. Seen in an oscilloscope, the domestic power supply in North America would look like a sine wave, oscillating between -170 volts and 170 volts, giving an effective voltage of 120 volts. Three-phase power is more efficient in terms of power delivered per cable used, and ismore suited to running large electric motors. Some large European appliances may be powered by three-phase power, such as electric stoves and clothes dryers.A ground connection is normally provided for the customer's system as well as for the equipment owned by the utility. The purpose of connecting the customer's system to ground is to limit the voltage that may develop if high voltage conductors fall down onto lower-voltage conductors which are usually mounted lower to the ground, or if a failure occurs within a distribution transformer. Earthing systems can be TT, TN-S, TN-C-S or TN-C.Regional variations220-240 volt systemsMost of the world uses 50 Hz single-phase 220 or 230 V residential and light industrial service. In this system, the primary distribution network supplies a few substations per area, and the 230 V power from each substation is directly distributed. A live (hot) wire and neutral are connected to the building from one phase of three phase service. Single-phase distribution is used where motor loads are light. In Europe, electricity is normally distributed for industry and domestic use by the three-phase, four wire system. This gives a three-phase voltage of 400 volts wye service and a single-phase voltage of 230 volts. For industrial customers, 3-phase 690 / 400 volt is also available. Large industrial customers have their own transformers with an input from 10kV to 220kV. In the UK a typical urban or suburban low-voltage substation would normally be rated between 315kV A and 1MV A and supply a whole neighborhood.110-120 volt systemsMost of the Americas use 60 Hz AC, the 120/240 volt split phase system domestically and three phase for larger installations. pared to European systems, North American ones have more step-down transformers near customers. This is because the higher domestic voltage used in Europe (230 V vs 120 V) may be carried over a greater distance with acceptable power loss.In the electricity sector in Japan, the standard frequencies for AC are 50 and 60 Hz. In Japan parts of the country use 50 Hz, while other parts use 60 Hz. This is a relic of the 1800s. Some local providers in Tokyo imported 50 Hz German equipment, while thelocal power providers in Osaka brought in 60 Hz generators from the United States. The grids grew until eventually the entire country was wired. Today the frequency is 50 Hz in Eastern Japan (including Tokyo, Yokohama, Tohoku, and Hokkaido) and 60 Hertz in Western Japan (including Nagoya, Osaka, Kyoto, Hiroshima, Shikoku, and Kyushu).Most household appliances are made to work on either frequency. The problem of inpatibility came into the public eye when the 20XX Tōhoku earthquake and tsunami knocked out about a third of the east’s capacity, and power in the west couldn’t be fully shared with the east, since the country does not have a mon frequency.There are four converter stations that move power across Japan’s AC frequency border. Shin Shinano is a back-to-back HVDC facility in Japan which forms one of four frequency changer stations that link Japan's western and eastern power grids. The other three are at Higashi-Shimizu, Minami-Fukumitsu and Sakuma Dam. Together they can move up to 1.2 GW of power east or west.原文出处:https:///wiki/Electric_power_distributionThree-phase electric powerThree-phase electric power is a mon method of alternating-current electric power generation, transmission, and distribution.It is a type of polyphase system and is the most mon method used by electrical grids worldwide to transfer power. It is also used to power large motors and other heavy loads. A three-phase system is usually more economical than an equivalent single-phase at the same line to ground voltage because it uses less conductor material to transmit electrical power. The three-phase system was independently invented by Galileo Ferraris, Mikhail Dolivo-Dobrovolsky, Jonas Wenström and Nikola Tesla in the late 1880s.PrincipleIn a symmetric three-phase power supply system, three conductors each carry an alternating current of the same frequency and voltage amplitude relative to a mon reference but with a phase difference of one third the period. The mon reference isusually connected to ground and often to a current-carrying conductor called the neutral. Due to the phase difference, the voltage on any conductor reaches its peak at one third of a cycle after one of the other conductors and one third of a cycle before the remaining conductor. This phase delay gives constant power transfer to a balanced linear load. It also makes it possible to produce a rotating magnetic field in an electric motor and generate other phase arrangements using transformers (For instance, a two phase system using a Scott-T transformer).The symmetric three‐phase systems described here are simply referred to as three‐phase systems because, although it is possible to design and implement asymmetric three‐phase power systems (i.e., with unequal voltages or phase shifts), they are not used in practice because they lack the most important advantages of symmetric systems.In a three‐phase system feeding a balanced and linear load, the sum of the instantaneous currents of the three conductors is zero. In other words, the current in each conductor is equal in magnitude to, but with the opposite sign of, the sum of the currents in the other two. The return path for the current in any phase conductor is the other two phase conductors.pared to a single-phase AC power supply that uses two conductors (phase and neutral), a three-phase supply with no neutral, the same phase-to-ground voltage and current capacity per phase can transmit three times as much power using just 1.5 times as many wires (i.e., three instead of two). Thus, the ratio of capacity to conductor material is doubled. The same (but not the other properties of three-phase power) can also be attained with a center-grounded single-phase system.Three-phase systems may also utilize a fourth wire, particularly in low-voltage distribution. This is the neutral wire. The neutral allows three separate single-phase supplies to be provided at a constant voltage and is monly used for supplying groups of domestic properties which are each single-phase loads. The connections are arranged so that, as far as possible in each group, equal power is drawn from each phase. Further up the distribution system, the currents are usually well balanced. Transformers may be wired in a way that they have a four‐wire secondary but a three‐wire primary whileallowing unbalanced loads and the associated secondary‐side neutral currents.Three-phase supplies have properties that make them very desirable in electric power distribution systems:The phase currents tend to cancel out one another, summing to zero in the case of a linear balanced load. This makes it possible to reduce the size of the neutral conductor because it carries little or no current. With a balanced load, all the phase conductors carry the same current and so can be the same size.Power transfer into a linear balanced load is constant, which helps to reduce generator and motor vibrations.Three-phase systems can produce a rotating magnetic field with a specified direction and constant magnitude, which simplifies the design of electric motors.Most household loads are single-phase.In North American residences, three-phase power might feed a multiple-unit apartment block, but the household loads are connected only as single phase. In lower-density areas, only a single phase might be used for distribution.Some large European appliances may be powered by three-phase power, such as electric stoves and clothes dryers.Wiring for the three phases is typically identified by color codes which vary by country. Connection of the phases in the right order is required to ensure the intended direction of rotation of three-phase motors. For example, pumps and fans may not work in reverse. Maintaining the identity of phases is required if there is any possibility two sources can be connected at the same time; a direct interconnection between two different phases is a short-circuit.原文出处:https:///wiki/Three-phase_electric_power。
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Power Supply and Distribution System ABSTRACT:The basic function of the electric power system is to transport the el ectric power towards customers.The l0kV electric distribution net is a key point that connects the power supply with the electricity usin g on the industry,business and daily-life.For the electric power,allc ostumers expect to pay the lowest price for the highest reliability,b ut don't consider that it's self-contradictory in the co-existence of ec onomy and reliable.To improve the reliability of the power supply n etwork,we must increase the investment cost of the network constr uction But,if the cost that improve the reliability of the network con struction,but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the inc reasing investment on improving the reliability.Thus we find out a b alance point to make the most economic,between the investment a nd the loss by calculating the investment on power net and the loss brought from power-off.KEYWORDS:power supply and distribution,power distribution reliability,reactive compensation,load distributionThe revolution of electric power system has brought a new big round construction,which is pushing the greater revolution of electric po wer technique along with the application of new technique and adv anced equipment.Especially,the combination of the information te chnique and electric power technique,to great ex-tent,has improv ed reliability on electric quality and electric supply.The technical de velopment decreases the cost on electric construction and drives in novation of electric network.On the basis of national and internatio -nal advanced electric knowledge,the dissertation introduces the r esearch hotspot for present electric power sy-etem as following.Firstly,This dissertation introduces the building condition of distribu tion automation(DA),and brings forward two typical construction m odes on DA construction,integrative mode and fission mode.It emp hasize the DA structure under the condition of the fission mode and presents the system configuration,the main station scheme,the fe eder scheme,the optimized communication scheme etc.,which is f or DA research reference.Secondly,as for the(DA)trouble measurement,position,isolation a nd resume,This dissertation analyzes the changes of pressure and c urrent for line problem,gets math equation by educing phase short circuit and problem position under the condition of single-phase and works out equation and several parameter s U&,s I&ande I&tab le on problem.It brings out optimized isolation and resume plan,re alizes auto isolation and network reconstruction,reduces the power off range and time and improves the reliability of electric power su pply through problem self-diagnoses and self-analysis.It also introd uces software flow and use for problem judgement and sets a mode l on network reconstruction and computer flow.Thirdly,electricity system state is estimated to be one of the key tec hniques in DA realization.The dissertation recommends the resolve nt of bad measurement data and structure mistake on the ground of describing state estimate way.It also advances a practical test and j udging way on topology mistake in state estimate about bad data te st and abnormity in state estimate as well as the problem and effect on bad data from state measure to state estimate.As for real time monitor and control problem,the dissertation introduces a new wa y to solve them by electricity break and exceptional analysis,and th e way has been tested in Weifang DA.Fourthly,about the difficulty for building the model of load forecasti ng,big parameter scatter limit and something concerned,the disser tation introduces some parameters,eg.weather factor,date type and social environment effect based on analysis of routine load foreca sting and means.It presents the way for electricity load forecastingf ounded on neural network(ANN),which has been tested it’s validity by example and made to be good practical effect.Fifthly,concerning the lack of concordant wave on preve nting conc ordant wave and non-power compensation and non-continuity on c ompensation,there is a topology structure of PWM main circuit and nonpower theory on active filter the waves technique and builds fla t proof on the ground of Saber Designer and proves to be practical. Meanwhile,it analyzes and designs the way of non-power need of e lectric network tre-nds and decreasing line loss combined with DA, which have been tested its objective economic benefit throu-gh co unting example.Sixthly,not only do the dissertation design a way founded on the m agrginal electric price fitted to our present national electric power market with regards to future trends of electric power market in Chi na and fair trade under the government surveillance,that is group c ompetitio n in short-term trade under the way of grouped price and quantity harmony,but also puts forward combination arithmetic,m ath model of trading plan and safty economical restriction.It can solve the original contradiction between medium and long term contra ct price and short term competitive price with improvement on com petitive percentage and cut down the unfair income difference of el ectric factory,at the same time,it can optimize the electric limit for all electric factories and reduce the total purchase charge of electric power from burthen curve of whole electric market network.The distribution network is an important link among the power syst em.Its neutral grounding mode and operation connects security an d stability of the power system directly.At the same time,the probl em about neutral grounding is associated with national conditions, natural environment,device fabrication and operation.For example, the activity situation of the thunder and lightning,insulating struct ure and the peripheral interference will influence the choice of neut ral grounding mode Conversely,neutral grounding mode affects desi gn,operation,debugs and developing.Generally in the system high er in grade in the voltage,the insulating expenses account for more sizable proportion at the total price of the equipment.It is very rem arkable to bring the economic benefits by reducing the insulating le ually such system adopt the neutral directly grounding and ad opt the autoreclosing to guarantee power supply reliability.On the c ontrary,the system which is lower in the voltage adopts neutral non e grounding to raise power supply reliability.So it is an important subject to make use of new-type earth device to apply to the distribut ion network under considering the situation in such factors of vario us fields as power supply reliability,safety factor,over-voltage factor, the choice of relay protection,investment cost,etc.The main work of this paper is to research and choice the neutral gr ounding mode of the l0kV distribution network.The neutral groundi ng mode of the l0kV network mainly adopts none grounding,groun ding by arc suppressing coil,grounding by reactance grounding and directly grounding.The best grounding mode is confirmed through t he technology comparison.It can help the network run in safety and limit the earth electric arc by using auto-tracking compensate devic e and using the line protection with the detection of the sensitive s mall ground current.The paper introduces and analyzes the charact eristic of all kind of grounding modes about l0kV network at first.Wi th the comparison with technological and economy,the conclusion i s drawn that the improved arc suppressing coil grounding mode sho ws a very big development potential.Then,this paper researches and introduces some operation charact eristics of the arc suppressing coil grounding mode of the l0kV distri bution network.And then the paper put emphasis on how to exting uish the earth electric arc effectively by utilizing the resonance principle.This paper combines the development of domestic and interna tional technology and innovative achievement,and introduces the c omputer earth protection and autotracking compensate device.It p roves that the improved arc suppressing coil grounding mode have better operation characteristics in power supply reliability,personal security,security of equipment and interference of communication. The application of the arc suppressing coil grounding mode is also re searched in this paper.Finally,the paper summarizes this topic research.As a result of the domination of the arc suppressing coil grounding mode,it should be more popularized and applied in the distribution network in the fut ure.The way of thinking,project and conclusions in this thesis have e ffect on the research to choose the neutral grounding mode not onl y in I0kV distribution network but also in other power system..The basic function of the electric power system is to transport the el ectric power towards customers.The l0kV electric distribution net is a key point that connects the power supply with the electricity usin g on the industry,business and daily-life.For the electric power,all c ostumers expect to pay the lowest price for the highest reliability,b ut don't consider that it's self-contradictory in the co-existence of ec onomy and reliable.To improve the reliability of the power supply network,we must increase the investment cost of the network con-s truction But,if the cost that improve the reliability of the network c onstruction,but the investment on this kind of construction would be worthless if the reducing loss is on the power-off is less than the increasing investment on improving the reliability.Thus we find out a balance point to make the most economic,between the investme nt and the loss by calculating the investment on power net and the l oss brought from power-off.The thesis analyses on the economic an d the reliable of the various line modes,according to the characteris tics various line modes existed in the electric distribution net in fosh an..First,the thesis introduces as the different line modes in the l0kV el ectric distribution net and in some foreign countries.Making it clear tow to conduct analyzing on the line mode of the electric distributi on net,and telling us how important and necessary that analyses ar e.Second,it turns to the necessity of calculating the number of optimi zation subsection,elaborating how it influences on the economy an d reliability.Then by building up the calculation mode of the numbe r of optimization subsection it introduces different power supply pr ojects on the different line modes in brief.Third,it carries on the cal culation and analyses towards the reliability and economy of the different line modes of electric distribution net,describing drafts accor ding by the calculation.Then it makes analysis and discussion on the number of optimization subsection.At last,the article make conclusion on the economy and reliability o f different line modes,as well as,its application situation.Accordion to the actual circumstance,the thesis puts forward the beneficial s uggestion on the programming and construction of the l0kV electric distribution net in all areas in foshan.Providing the basic theories a nd beneficial guideline for the programming design of the10kV elec tric distribution net and building up a solid net,reasonable layout,q ualified safe and efficiently-worked electric distribution net.。