外文翻译--电力电子系统的电磁兼容问题
英语作文-如何进行集成电路设计中的电磁兼容与抗干扰设计

英语作文-如何进行集成电路设计中的电磁兼容与抗干扰设计Electromagnetic compatibility (EMC) and electromagnetic interference (EMI) are crucial aspects in the design of integrated circuits (ICs). In order to ensure the proper functioning of electronic devices, it is essential to address these issues during the design phase. This article will discuss the key considerations and techniques for achieving EMC and EMI design in integrated circuit design.1. Grounding and Shielding:One of the primary steps in EMC and EMI design is to establish a robust grounding system. Proper grounding helps in minimizing the noise and interference in the circuit. It is important to create a low impedance path for the flow of current and to ensure that the ground plane is continuous and properly connected. Shielding techniques, such as using conductive enclosures or adding shielding layers, can also be employed to minimize electromagnetic radiation and external interference.2. Signal Integrity:Maintaining signal integrity is crucial for EMC and EMI design. High-speed signals are prone to noise and interference, which can result in signal degradation. Techniques such as impedance matching, proper termination, and controlled impedance routing should be implemented to minimize signal reflections and ensure signal integrity. Careful consideration should be given to the layout and routing of high-speed traces to minimize crosstalk and electromagnetic radiation.3. Power Integrity:Power distribution network (PDN) design plays a vital role in EMC and EMI design. Proper decoupling capacitors should be placed strategically to suppress power supply noise and voltage fluctuations. The PDN should be designed to minimize the loop area and inductance, as high loop inductance can result in voltage spikes and noise. Groundbounce and power rail collapse should be minimized through careful power distribution network design.4. Filtering and EMI Suppression:The use of appropriate filtering techniques is essential to suppress electromagnetic interference. Passive components such as ferrite beads, capacitors, and inductors can be used to filter out unwanted noise and interference. Differential signaling and common-mode chokes can also be employed to reduce EMI. It is important to analyze the frequency spectrum and identify the specific frequencies to be filtered out.5. ESD Protection:Electrostatic discharge (ESD) can cause significant damage to ICs. Implementing proper ESD protection measures is crucial to ensure the reliability and longevity of integrated circuits. ESD protection devices, such as diodes and transient voltage suppressors, should be incorporated into the design to divert and dissipate electrostatic discharge safely.6. Simulation and Testing:Simulation and testing are essential steps in EMC and EMI design. Various simulation tools can be used to analyze and optimize the design for electromagnetic compatibility. Testing the ICs under different operating conditions and environmental scenarios is necessary to ensure compliance with EMC standards. This includes radiated and conducted emission tests, as well as susceptibility tests.In conclusion, achieving electromagnetic compatibility and mitigating electromagnetic interference in integrated circuit design is crucial for the proper functioning and reliability of electronic devices. By following proper grounding and shielding techniques, ensuring signal and power integrity, implementing effective filtering and ESD protection, and conducting thorough simulation and testing, designers can achieve optimal EMC and EMI design in integrated circuits.。
电磁兼容与电磁干扰

电磁兼容与电磁干扰电磁兼容与电磁干扰(Electromagnetic Compatibility and Electromagnetic Interference,简称EMC/EMI)是当今电磁环境下普遍存在的问题。
随着现代电子技术的快速发展,各类电子设备的广泛应用,电磁兼容与电磁干扰问题也日益显著。
本文将就电磁兼容与电磁干扰进行探讨和分析,以期提供一定的理论指导和实践经验。
一、电磁兼容电磁兼容是指在特定的电磁环境下,电子设备能够正常地工作,同时与其它电子设备和环境保持协调。
换句话说,电磁兼容要求电子设备不会由于电磁场的存在而产生损坏或干扰其他设备的工作,同时也不会受到外部电磁干扰的影响。
在实际生产过程中,为了保证电子设备的电磁兼容性,我们需要进行各项测试和分析。
主要包括电磁辐射测试、电磁抗扰度测试、电磁传导干扰测试等。
只有经过这些测试,我们才能够确保设备在各种电磁环境下正常工作。
另外,制定合理的电磁兼容性规范和标准也是非常必要的。
二、电磁干扰电磁干扰是指电磁场对电子设备正常工作的干扰。
一般分为辐射干扰和传导干扰两类。
辐射干扰是指电子设备本身产生的电磁波辐射到周围空间,造成其他设备的工作异常或者产生故障。
为了减少辐射干扰,我们需要对电子设备进行合理设计,采取电磁屏蔽措施,并遵循相关的规范和标准。
传导干扰是指外部电磁场通过传导途径进入设备内部,引起设备的工作异常或产生故障。
为了减少传导干扰,我们可以采取适当的阻抗匹配和屏蔽措施,以降低外部电磁场对设备的影响。
针对电磁干扰问题,我们需要从整个系统的角度进行综合分析和研究,找出可能引起干扰的关键因素,并采取相应的措施进行干扰抑制和干扰消除。
三、电磁兼容与电磁干扰的重要性电磁兼容与电磁干扰的问题不容忽视,其重要性主要体现在以下几个方面:1. 保证电子设备的正常工作。
在日常生活和生产中,我们离不开各式各样的电子设备。
只有保证电子设备能够正常工作,才能够满足人们的需求,推动社会经济的发展。
电力系统中的电磁兼容设计与优化

电力系统中的电磁兼容设计与优化随着电力系统的不断发展和完善,电力设备的数量和种类也越来越多,而这些设备中均存在电磁辐射和电磁干扰的问题。
电磁兼容(Electromagnetic Compatibility,EMC)设计与优化是电力系统中一个重要的方面,它涉及到电磁波的传播、辐射和接收,以及对其他电子设备的干扰和抗干扰能力。
一、电磁兼容的基本概念在电力系统中,电器设备包括发电机、变压器、开关设备、电缆、电动机等,都会通过电磁辐射和电磁干扰与其他设备进行相互作用。
为了保证电力系统的正常工作和其他设备的正常运行,电磁兼容设计就显得尤为重要。
电磁兼容的基本概念是指在电力系统中,各种电磁设备和设施之间相互兼容,互相不对其造成干扰,使电力系统保持良好的电磁环境,并确保电力系统具备良好的抗干扰和抗辐射能力。
具体包括:电磁干扰的抑制、电磁辐射的控制、电磁敏感性的降低以及电磁抗扰能力的提高。
二、电磁兼容设计的原则1. 路由设计原则路由设计是电磁兼容的重要环节。
在电力系统的设计中,应尽量采用合理的电磁兼容路由来布置线路和设备,防止电磁辐射和传导的产生和传播,从而降低对其他设备的干扰和抗扰能力。
2. 接地系统设计原则接地系统是电磁兼容设计的一个重要组成部分。
它主要是为了疏导、消除和减轻设备和系统中产生的电磁干扰,保持合适的接地电位和电压。
因此,接地系统的设计需要合理规划和配置地线、大地电极、接地网等元件,确保接地电阻和接地电位满足要求。
3. 屏蔽设计原则屏蔽设计是电磁兼容设计的重要手段之一,它通过将电子设备和设施置于恰当的屏蔽措施下,以防止电磁辐射的产生和电磁干扰的传播。
屏蔽设计可以采用金属屏蔽、电磁屏蔽罩、屏蔽隔离等方式,提高设备和电路的抗干扰和抗辐射能力。
4. 接线布线设计原则接线布线设计是电磁兼容设计的重要环节,它主要涉及到信号传输线路的布置、电缆的配线和连接方式的选择等。
在接线布线设计中,应遵循路径短、布线整齐、信号线和电源线分隔、避免共模干扰源等原则,减小电磁辐射和传导的产生和传播。
电气类外文翻译---电力电子系统的电磁兼容问题

外文资料译文Power Electronics Electromagnetic CompatibilityThe electromagnetic compatibility issues in power electronic systems are essentially the high levels of conducted electromagnetic interference (EMI) noise because of the fast switching actions of the power semiconductor devices. The advent of high-frequency, high-power switching devices resulted in the widespread application of power electronic converters for human productions and livings. The high-power rating and the high-switching frequency of the actions might result in severe conducted EMI. Particularly, with the international and national EMC regulations have become more strictly, modeling and prediction of EMI issues has been an important research topic.By evaluating different methodologies of conducted EMI modeling and prediction for power converter systems includes the following two primary limitations: 1) Due to different applications, some of the existing EMI modeling methods are only valid for specific applications, which results in inadequate generality. 2) Since most EMI studies are based on the qualitative and simplified quantitative models, modeling accuracy of both magnitude and frequency cannot meet the requirement of the full-span EMI quantification studies, which results in worse accuracy. Supported by National Natural Science Foundation of China under Grant 50421703, this dissertation aims to achieve an accurate prediction and a general methodology. Several works including the EMI mechanisms and the EMI quantification computations are developed for power electronic systems. The main contents and originalities in this research can be summarized as follows.I. Investigations on General Circuit Models and EMI Coupling ModesIn order to efficiently analyze and design EMI filter, the conducted EMI noise is traditional decoupled to common-mode (CM) and differential-mode (DM) components. This decoupling is based on the assumption that EMI propagation paths have perfectly balanced and time-invariant circuit structures. In a practical case, power converters usually present inevitable unsymmetrical or time-variant characteristics due to the existence of semiconductor switches. So DM and CM components can not be totally decoupled and they can transform to each other. Therefore, the mode transformation led to another new mode of EMI: mixed-mode EMI. In order to understand fundamental mechanisms by which the mixed-mode EMI noise is excited and coupled, this dissertation proposes the general concept of lumped circuit model for representing the EMI noise mechanism for power electronic converters. The effects of unbalanced noise source impedances on EMI mode transformation are analyzed. The mode transformations between CM and DM components are modeled. The fundamental mechanism of the on-intrinsic EMI is first investigated for a switched mode power supply converter. In discontinuous conduction mode, the DM noise is highly dependent on CM noise because of the unbalanced diode-bridge conduction. It is shown that with the suitable and justifiedmodel, many practical filters pertinent to mixed-mode EMI are investigated, and the noise attenuation can also be derived theoretically. These investigations can provide a guideline for full understanding of the EMI mechanism and accuracy modeling in power electronic converters. (Publications: A new technique for modeling and analysis of mixed-mode conducted EMI noise, IEEE Transactions on Power Electronics, 2004; Study of differential-mode EMI of switching power supplies with rectifier front-end, Transactions of China Electro technical Society, 2006)II. Identification of Essential Coupling Path Models for Conducted EMI Prediction Conducted EMI prediction problem is essentially the problem of EMI noise source modeling and EMI noise propagation path modeling. These modeling methods can be classified into two approaches, mathematics-based method and measurement-based method. The mathematics method is very time-consuming because the circuit models are very complicated. The measurement method is only valid for specific circuit that is conveniently to be measured, and is lack of generality and impracticability. This dissertation proposes a novel modeling concept, called essential coupling path models, derived from a circuit theoretical viewpoint, means that the simplest models contain the dominant noise sources and the dominant noise coupling paths, which can provide a full feature of the EMI generations. Applying the new idea, this work investigates the conducted EMI coupling in an AC/DC half-bridge converter. Three modes of conducted EMI noise are identified by time domain measurements. The lumped circuit models are derived to describe the essential coupling paths based on the identification of the EMI coupling modes. Meanwhile, this study illustrates the extraction of the parameters in the afore-described models by measurements, and demonstrates the significance of each coupling path in producing conducted EMI. It is shown that the proposed method is very effective and accurate in identifying and capturing EMI features. The equivalent models of EMI noise are sorted out by just a few simple measurements. Under these approaches, EMI performance can be predicted together with the filtering strategies. (Publications: Identification of essential coupling path models for conducted EMI prediction in switching power converters, IEEE Transactions on Power Electronics, 2006; Noise source lumped circuit modeling and identification for power converters, IEEE Transactions on Industrial Electronics, 2006)III. High Frequency Conducted EMI Source ModelingThe conventional method of EMI prediction is to model the current or voltage source as a periodic trapezoidal pulse train. However, the single slope approximation for rise and fall transitions can not characterize the real switching transitions involved in high frequency resonances. In most common noise source models simple trapezoidal waveforms are used where the high frequency information of the EMI spectrum is lost. Those models made several important assumptions which greatly impair accuracy in the high frequency range of conducted noise. To achieve reasonable accuracy for EMI modeling at higher frequencies, the relationship between the switching transitions modeling and the EMI spectrum is studied. An important criterion is deduced to give the reasonable modeling frequency range for the traditional simple approximation method. For the first time, an improved and simplified EMI source modeling methodbased on multiple slope approximation of device switching transitions is presented. To confirm the proposed method, a buck circuit prototype using an IGBT module is implemented. Compared with the superimposed envelops of the measured spectra, it can be seen that the effective modeling frequency is extended to more than 10 MHz, which verifies that the proposed multiple slopes switching waveform approximation method can be applied for full-span EMI noise quantification studies. (Publications: Multiple slope switching waveform approximation to improve conducted EMI spectral analysis of power converters, IEEE Transactions on Electromagnetic Compatibility, 2006; Power converter EMI analysis including IGBT nonlinear switching transient model, IEEE Transactions on Industrial Electronics, 2006)IV. Loop Coupling EMI Modeling in Power Electronic SystemsPractical examples of power electronic systems that have various electrical, electromechanical and electronics apparatus emit electromagnetic energy in the course of their normal operations. In order to predict the EMI noise in a system level, it is significant to model the EMI propagation characteristics through electromagnetic coupling between two apparatus circuit within a power electronic system. The PEEC modeling technique which was first introduced in 1970s has recently becomes a popular choice in relation to the electromagnetic analysis and EMI coupling. In previous studies, the integral equation based method was mostly applied in the electrical modeling and analysis of the interconnect structure in very large scale integration systems, only at the electronic chip and package level. By introducing the partial inductance theory of PEEC modeling technique, this work investigates the EMI loop coupling issues in power electronic circuits. The work models the magnetic flux coupling due to EMI current on one conductor and another by mutual inductance. To model the EMI coupling between the grounding circuits, this study divides the ground impedance into two parts: one is the internal impedance and the other is the external inductance. The external inductance due to the fields external to the rectangular grounding loop and flat conductor is modeled. To verify the mathematical models, the steel plane grounding test configurations are constructed and the DM and CM EMI coupling generation and modeling technique are experimentally studied. The comparison between the measured and calculated EMI noise voltage validates the proposed analysis and models. These investigations and results can provide a powerful engineering application of analyzing and solving the coupling EMI issues in power electronic circuits and systems. (This part of work is one of the main contributions of the awarded project of Military Science and Technology Award in 2006, where the author is No. 4 position. Publication: Loop coupled EMI analysis based on partial inductance models, Proceedings of the Chinese Society of Electrical Engineering, 2007)V. Conducted EMI Prediction for PWM Conversion UnitsPWM-based power conversion units are the main EMI noise sources in power systems. Due to the various PWM strategies and the large number of switches, a common analytical approach for the PWM-based switched converter systems has not been dated. Determination of the frequency spectrum of a PWM converter is quite complex and is often done by using an FFT analysis of a simulated time-varyingswitched waveform. This approach requires considerable computing capacity and always leaves the uncertainty as to whether a subtle simulation round-off or error may have slightly tarnished the results obtained. By introducing the principle of the double Fourier integral, this work presents a general method for modeling the conduced EMI sources of PWM conversion units by identifying double integral Fourier form to suit each PWM modulation. Appling the proposed method, three PWM strategies have been discussed. The effects of different modulation schemes on EMI spectrum are evaluated. The EMI modeling and prediction efforts from an industrial application system are studied comprehensively. Comparison between the measured and the predicted spectrum confirms the validity of the EMI modeling and prediction method. This method breaks through the limitations of time-consuming and considerable accumulated error by traditional time-domain simulations. A standard without relying on simulation but a common analytical approach has been obtained. Clearly, it can be regarded as a common analytical approach that would be useful to be able to model and predict the exact EMI performance of the PWM-based power electronic systems. (Publications: DM and CM EMI Sources Modeling for Inverters Considering the PWM Strategies, Transactions of China Electro technical Society, 2007. High Frequency Model of Conducted EMI for PWM Variable-speed Drive Systems, Proceedings of the Chinese Society of Electrical Engineering, 2008)电力电子系统的电磁兼容问题电力电子系统的电磁兼容问题,集中体现为半导体器件的开关工作方式产生的传导性电磁干扰(EMI)。
电力电子系统的EMC问题与解决方案

电力电子系统的EMC问题与解决方案电力电子系统的电磁兼容(Electromagnetic Compatibility,简称EMC)问题是指在电磁环境下,电力电子系统正常工作所需的电磁环境条件,以及电力电子系统对外界电磁环境的产生的电磁干扰的抵抗能力。
在电力电子系统的设计和应用过程中,EMC问题是一个不可避免的挑战。
本文将介绍电力电子系统的EMC问题,并探讨一些解决方案。
一、电力电子系统的EMC问题电力电子系统在运行过程中会产生电磁波,这些电磁波会辐射到周围环境中,对其他设备和系统产生干扰。
同时,电力电子系统也会受到来自外部电磁波的干扰,影响其正常工作。
这些问题都属于电力电子系统的EMC问题。
1. 电磁辐射问题电力电子系统在工作时会产生高频电磁波,如开关电源、变频器和整流器等,这些高频电磁波会通过导线、辐射、波导等途径传播到周围环境中,对其他设备和系统造成干扰。
特别是在无线通信系统和医疗设备等对电磁波敏感的环境中,电磁辐射问题尤为重要。
2. 电磁感受问题电力电子系统对外界电磁波的感受性也是一个重要问题。
当电力电子系统暴露在高强度电磁场的环境中时,会受到来自电磁波的干扰,从而影响其正常工作。
例如,在雷电或强磁场环境下,电力电子系统可能会出现故障或损坏。
二、解决电力电子系统的EMC问题的方案为了解决电力电子系统的EMC问题,需要采取一系列的技术手段和措施。
以下是一些常见的解决方案:1. 地线设计地线是电力电子系统中的重要部分,它能够消除电磁干扰并提高系统的EMC性能。
在地线设计中,需要合理布置和连接地线,建立良好的接地系统,使系统的电磁能量得到合理的分配和消耗,从而减少电磁辐射和提高抗干扰能力。
2. 滤波器设计在电力电子系统中安装滤波器可以有效地减少电磁辐射和抑制电磁干扰。
滤波器能够在电源和负载之间形成一个衰减效应,阻止高频电磁波的传播,从而减少对其他设备的干扰。
3. 接地设计良好的接地设计能够有效地降低电磁辐射和提高系统的抗干扰能力。
电磁兼容整改措施__概述及解释说明

电磁兼容整改措施概述及解释说明1. 引言1.1 概述电磁兼容(Electromagnetic Compatibility,简称EMC)是指在复杂电磁环境下,各种电子设备和系统能够正常工作,并且不会对周围环境和其他设备产生不可接受的干扰。
随着科技的快速发展和广泛应用,电磁兼容性问题日益突出,给人们的日常生活、工业生产以及航空航天等领域带来了许多挑战。
1.2 文章结构本文主要分为五个部分。
首先,在引言中将介绍电磁兼容整改措施的概述以及文章的结构;其次,在第二部分中阐述了电磁兼容整改措施的解释说明,包括对电磁兼容概念进行解释、分析电磁干扰问题产生原因以及为何需要采取整改措施;第三部分将对电磁兼容整改措施进行分类和方法论述,涉及线缆布置与屏蔽处理相关措施、地线设计和接地处理相关措施以及EMI滤波器和抑制器的应用措施;第四部分将通过具体案例,提供电磁兼容整改措施的实施细节和分析;最后,在结论部分总结了电磁兼容整改的重要性、整改措施实施对产品或系统绩效的影响以及未来发展趋势和挑战。
1.3 目的本文的目的是介绍和解释电磁兼容整改措施的基本概念与原理,为读者提供一种了解和应用这些措施的方法。
通过深入理解电磁兼容整改问题,读者可以有效地识别和解决相关问题,并采取相应的措施来确保设备和系统在复杂电磁环境中的正常运行。
2. 电磁兼容整改措施解释说明:2.1 电磁兼容概念解释电磁兼容指的是在电子设备或系统中,各种不同的电子设备能够在不产生互相干扰或受到外界干扰的情况下协同工作的能力。
在现代科技发展中,电子设备越来越复杂,频谱资源日益紧张,因此保持良好的电磁兼容性显得尤为重要。
2.2 电磁干扰问题分析在电子设备中,存在着各种类型的电磁场,包括辐射、传导和导耦等。
这些电磁场可能会对其他附近的设备或系统造成干扰,导致无法正常工作或降低性能。
例如,在无线通信系统中,如果存在强大的脉冲噪声源,则可能会引起接收器敏感度下降或信号质量恶化。
电磁兼容(EMC)专用术语

电磁兼容(EMC)专用术语电磁环境 electromagnetic environment在于给定场所的所有电磁现象的总和。
电磁噪声 electromagnetic noise额定电流是指在规定频率及电压下,环境温度为 40 ℃时滤波器可通过的安全允许电流。
无用信号 unwanted signal,undesired signal可能损害有用信号接收的信号。
电磁骚扰 electromagnetic disturbance任何可能引起装置设备或系统性能降低或对有生命或无生命物质产生损害作用的电磁现象。
注:电磁骚扰可能是电磁噪声、无用信号或传播媒介自身的变化。
电磁干扰 electromagnetic interference(EMI)电磁骚扰引起的设备、传输通道或系统性能的下降。
电磁兼容性 electromagnetic compatibility(EMC)设备或系统在其电磁环境中能正常工作且不对该环境中任何事物构成不能承受的电磁骚扰的能力。
(电磁)发射 (electromagnetic) emission从源向外发出电磁能的现象。
(无线电通信中的)发射 emission (in radio communication )由无线电发射台产生并向外发出无线电波或信号的现象。
(电磁)辐射 (electromagnetic)radiation能量以电磁波形式由源发射到空间的现象。
能量以电磁波形式在空间传播。
注:“电磁辐射”一词的含义有时也可引申,将电磁感应现象也包括在内。
无线电环境 radio environment无线电频率范围内的电磁环境在给定场所内所有处于工作状态的无线电发射机产生的电磁场总和。
无线电(频率)噪声 radio (frequency) noise具有无线电频率分量的电磁噪声。
无线电(频率)骚扰 radio (frequency) disturbance具有无线电频率分量的电磁骚扰。
无线电频率干扰 radio frequency interference(RFI)由无线电骚扰引起的有用信号接收性能的下降。
电气 自动化 外文文献 外文翻译 英文文献

外文出处:Farhadi, A. (2008). Modeling, simulation, and reduction of conducted electromagnetic interference due to a pwm buck type switching power supply. Harmonics and Quality of Power, 2008. ICHQP 2008. 13th International Conference on, 1 - 6.Modeling, Simulation, and Reduction of Conducted Electromagnetic Interference Due to a PWM Buck Type Switching Power Supply IA. FarhadiAbstract:Undesired generation of radiated or conducted energy in electrical systems is called Electromagnetic Interference (EMI). High speed switching frequency in power electronics converters especially in switching power supplies improves efficiency but leads to EMI. Different kind of conducted interference, EMI regulations and conducted EMI measurement are introduced in this paper. Compliancy with national or international regulation is called Electromagnetic Compatibility (EMC). Power electronic systems producers must regard EMC. Modeling and simulation is the first step of EMC evaluation. EMI simulation results due to a PWM Buck type switching power supply are presented in this paper. To improve EMC, some techniques are introduced and their effectiveness proved by simulation.Index Terms:Conducted, EMC, EMI, LISN, Switching SupplyI. INTRODUCTIONFAST semiconductors make it possible to have high speed and high frequency switching in power electronics []1. High speed switching causes weight and volume reduction of equipment, but some unwanted effects such as radio frequency interference appeared []2. Compliance with electromagnetic compatibility (EMC) regulations is necessary for producers to present their products to the markets. It is important to take EMC aspects already in design phase []3. Modeling and simulation is the most effective tool to analyze EMC consideration before developing the products. A lot of the previous studies concerned the low frequency analysis of power electronics components []4[]5. Different types of power electronics converters are capable to be considered as source of EMI. They could propagate the EMI in both radiated and conducted forms. Line Impedance Stabilization Network (LISN) is required for measurement and calculation of conducted interference level []6. Interference spectrum at the output of LISN is introduced as the EMC evaluation criterion []7[]8. National or international regulations are the references forthe evaluation of equipment in point of view of EMC []7[]8.II. SOURCE, PATH AND VICTIM OF EMIUndesired voltage or current is called interference and their cause is called interference source. In this paper a high-speed switching power supply is the source of interference.Interference propagated by radiation in area around of an interference source or by conduction through common cabling or wiring connections. In this study conducted emission is considered only. Equipment such as computers, receivers, amplifiers, industrial controllers, etc that are exposed to interference corruption are called victims. The common connections of elements, source lines and cabling provide paths for conducted noise or interference. Electromagnetic conducted interference has two components as differential mode and common mode []9.A. Differential mode conducted interferenceThis mode is related to the noise that is imposed between different lines of a test circuit by a noise source. Related current path is shown in Fig. 1 []9. The interference source, path impedances, differential mode current and load impedance are also shown in Fig. 1.B. Common mode conducted interferenceCommon mode noise or interference could appear and impose between the lines, cables or connections and common ground. Any leakage current between load and common ground couldbe modeled by interference voltage source.Fig. 2 demonstrates the common mode interference source, common mode currents Iandcm1 and the related current paths[]9.The power electronics converters perform as noise source Icm2between lines of the supply network. In this study differential mode of conducted interference is particularly important and discussion will be continued considering this mode only.III. ELECTROMAGNETIC COMPATIBILITY REGULATIONS Application of electrical equipment especially static power electronic converters in different equipment is increasing more and more. As mentioned before, power electronics converters are considered as an important source of electromagnetic interference and have corrupting effects on the electric networks []2. High level of pollution resulting from various disturbances reduces the quality of power in electric networks. On the other side some residential, commercial and especially medical consumers are so sensitive to power system disturbances including voltage and frequency variations. The best solution to reduce corruption and improve power quality is complying national or international EMC regulations. CISPR, IEC, FCC and VDE are among the most famous organizations from Europe, USA and Germany who are responsible for determining and publishing the most important EMC regulations. IEC and VDE requirement and limitations on conducted emission are shown in Fig. 3 and Fig. 4 []7[]9.For different groups of consumers different classes of regulations could be complied. Class Afor common consumers and class B with more hard limitations for special consumers are separated in Fig. 3 and Fig. 4. Frequency range of limitation is different for IEC and VDE that are 150 kHz up to 30 MHz and 10 kHz up to 30 MHz respectively. Compliance of regulations is evaluated by comparison of measured or calculated conducted interference level in the mentioned frequency range with the stated requirements in regulations. In united European community compliance of regulation is mandatory and products must have certified label to show covering of requirements []8.IV. ELECTROMAGNETIC CONDUCTED INTERFERENCE MEASUREMENTA. Line Impedance Stabilization Network (LISN)1-Providing a low impedance path to transfer power from source to power electronics converter and load.2-Providing a low impedance path from interference source, here power electronics converter, to measurement port.Variation of LISN impedance versus frequency with the mentioned topology is presented inFig. 7. LISN has stabilized impedance in the range of conducted EMI measurement []7.Variation of level of signal at the output of LISN versus frequency is the spectrum of interference. The electromagnetic compatibility of a system can be evaluated by comparison of its interference spectrum with the standard limitations. The level of signal at the output of LISN in frequency range 10 kHz up to 30 MHz or 150 kHz up to 30 MHz is criterion of compatibility and should be under the standard limitations. In practical situations, the LISN output is connected to a spectrum analyzer and interference measurement is carried out. But for modeling and simulation purposes, the LISN output spectrum is calculated using appropriate software.基于压降型PWM开关电源的建模、仿真和减少传导性电磁干扰摘要:电子设备之中杂乱的辐射或者能量叫做电磁干扰(EMI)。
电气工程中的电磁兼容性研究

电气工程中的电磁兼容性研究在当今科技飞速发展的时代,电气工程领域取得了令人瞩目的成就。
从电力系统的稳定运行到电子设备的高效工作,无一不依赖于电气技术的不断进步。
然而,在这个过程中,一个重要但往往被忽视的问题逐渐凸显出来,那就是电磁兼容性(Electromagnetic Compatibility,简称 EMC)。
电磁兼容性指的是电气设备或系统在其电磁环境中能正常工作,且不对该环境中任何事物构成不能承受的电磁骚扰的能力。
简单来说,就是各种电气设备在共同的电磁环境中能够和谐共处,互不干扰。
这一概念看似简单,实则包含了复杂的物理现象和技术要求。
在电气工程中,电磁兼容性问题的产生有着多方面的原因。
首先,随着电子设备的日益普及和集成化程度的提高,设备内部的电路密度不断增大,工作频率也越来越高。
这使得电磁辐射和电磁感应现象变得更加显著,从而增加了电磁干扰的可能性。
其次,电气系统的规模不断扩大,不同类型的设备和线路相互交织,形成了复杂的电磁网络。
如果在设计和规划阶段没有充分考虑电磁兼容性,就很容易导致设备之间的相互干扰。
电磁干扰的危害不容小觑。
在电力系统中,电磁干扰可能会引起继电保护装置的误动作,导致电网故障甚至停电事故。
对于通信系统,电磁干扰会降低信号的质量,影响通信的可靠性和稳定性。
在医疗设备中,电磁干扰可能会导致设备故障,甚至危及患者的生命安全。
在航空航天领域,电磁兼容性问题更是关系到飞行安全的重大问题。
为了确保电气系统的电磁兼容性,需要从多个方面采取措施。
在设备的设计阶段,就应当考虑电磁兼容性的要求。
这包括合理布局电路、选择合适的电子元件、采用屏蔽和滤波技术等。
例如,在电路板设计中,可以通过合理的布线减少电磁辐射和感应;使用屏蔽罩可以有效地阻挡外部电磁场对敏感电路的干扰;而滤波器则可以滤除电源和信号线上的杂波。
在系统集成阶段,需要对整个电气系统进行电磁兼容性测试。
这包括辐射发射测试、传导发射测试、辐射抗扰度测试和传导抗扰度测试等。
电气工程中的电磁兼容规范要求与应对策略

电气工程中的电磁兼容规范要求与应对策略电磁兼容(Electromagnetic Compatibility,简称EMC)是电气工程中一个重要的概念。
它涉及到电子设备和系统在同一空间内运行时所产生的电磁干扰和敏感度问题。
为了保证电子设备和系统可以在不产生电磁干扰或受到干扰的情况下正常运行,电磁兼容规范和相应的应对策略显得尤为重要。
一、电磁兼容规范要求电磁兼容规范是指对电子设备和系统的设计、制造、安装和使用过程中的电磁干扰问题进行规范和约束的文件。
这些规范通常是由国际、国家或行业组织制定的,旨在保证设备和系统能够在电磁环境下共存并正常工作。
1. 抗干扰能力要求电磁兼容规范中常对设备的抗干扰能力进行要求。
这一要求主要包括设备的抗辐射干扰(Radiated Disturbance)和抗传导干扰(Conducted Disturbance)能力。
抗辐射干扰是指设备对于电磁波的敏感性,抗传导干扰则是指设备对于传导途径中的电磁干扰的抵抗能力。
2. 发射限值要求为了保证设备在运行时不对其他设备和系统造成干扰,电磁兼容规范中通常会对设备发射的电磁辐射限值进行要求。
这些限值要求设备在指定频段内的发射功率不超过规定的阈值,以免对其他设备造成电磁干扰。
3. 灵敏度要求电磁兼容规范也会对设备的灵敏度进行要求。
设备的灵敏度是指设备受到外界电磁干扰时产生故障的可能性。
规范通常要求设备在一定的电磁干扰下仍能正常运行,以保证设备的可靠性。
二、应对策略为了满足电磁兼容规范的要求,需要采取一系列的应对策略。
1. 设备屏蔽设备屏蔽是指对设备进行设计和制造时,采取一定的屏蔽措施,以减少设备辐射和接收到的外界干扰。
常见的屏蔽措施包括在设备外壳内部涂覆屏蔽材料、使用屏蔽罩或屏蔽壳等。
2. 过滤器的使用过滤器是一种常用的抗干扰措施。
它可以将传导途径中的电磁干扰滤除,以保证设备正常工作。
常见的过滤器包括串联滤波器和并联滤波器等。
3. 接地和接线良好的接地和接线是保证电磁兼容的关键。
电路中的电磁兼容性与抗干扰设计

电路中的电磁兼容性与抗干扰设计电磁兼容性(Electromagnetic Compatibility,简称EMC)与抗干扰设计在电路领域中起着至关重要的作用。
电磁兼容性指的是电子设备在工作状态下,能够和其他电子设备以及电磁环境相互协调工作,而不会产生互相干扰或者被干扰的现象。
抗干扰设计则是指在电路设计过程中采取一系列措施,以降低设备受到外界电磁干扰的能力以及设备对其他电子设备造成的干扰。
一、电磁兼容性原理电磁兼容性的实现需要考虑两个方面,即电磁辐射和电磁敏感性。
电磁辐射是指设备在工作时所产生的电磁波通过空间传播,可能对周围的设备产生干扰。
电磁敏感性则是指设备对来自其他设备或者外界电磁场的干扰信号产生的相应。
要保证设备的兼容性,需要在设计过程中考虑这两个方面。
为了满足电磁兼容性的要求,设计师需要进行以下工作:1. 电磁辐射控制:通过合理布局,减少电路中的回路面积,降低电流回路的长度,采用屏蔽技术等方法,控制电磁辐射功率的大小,使其在国际标准规定的范围内。
2. 电磁敏感性控制:通过合理设计,采用屏蔽技术,减少设备对来自外界电磁场的敏感度,降低设备对干扰信号的响应。
3. 地线布局:良好的地线布局能够减少地线串扰,提高系统的抗干扰能力。
这包括合理的地线引出方法,减少地线共振等。
4. 滤波器的应用:在电路中加入滤波器能够减少电源线上的高频干扰,并降低设备的辐射噪声。
5. 屏蔽的使用:采用金属盖、金属屏蔽壳等方法,将设备的敏感部分与外界隔离,减少干扰的传播。
二、抗干扰设计的实施1. 设备的框架结构设计:在设备的设计中,应该合理布局各个电路部分,避免电路之间的相互干扰。
对于敏感部分应该采取隔离措施。
2. 电源线设计:电源线是设备中一个重要的噪声源,合理的电源线设计可以有效降低干扰对设备造成的影响。
包括电源线的滤波、地线的设计等。
3. 地线设计:地线是保证设备安全运行的重要组成部分,合理的地线设计可以降低设备对外部干扰的敏感性,防止干扰信号进入设备。
《电磁兼容》课程教学大纲(本科)

《电磁兼容》课程教学大纲课程编号:08115111课程名称:电磁兼容英文名称:Electromagnetic Compatibility课程类型:专业课课程要求:选修学时/学分:32/2(讲课学时:26 实验学时:6 )适用专业:电气工程及其自动化一、课程性质与任务电容兼容课程涵盖电路、电磁场、电机学、模拟电子技术、数字电子技术、单片机原理、电力电子技术、电力系统及电气传动等多门课程,是电气工程及其自动化专业的专业课,使电气工程及其自动化专业的学生掌握电力电子装置、电子线路等硬件、结构及电磁兼容抑制措施的综合设计能力。
本课程在教学内容方面将多门课程进行交叉,着重基础知识、基本理论及典型案例的讲解,在实践能力方面着重培养学生的独立设计能力,使学生具备一定的设计电力电子、电子线路硬件的能力。
二、课程与其他课程的联系先修课程:《电路》、《电磁场》、《电机学》、《模拟电子技术》、《数字电子技术》、《单片机原理》、《电力电子技术》、《电力系统》及《电气传动》等。
三、课程教学目标1.通过本课程的学习,使学生掌握电磁兼容的基本原理;熟悉电磁兼容的基本技术;了解电磁兼容的标准、强制认证要求及电磁兼容在电气、电子产品设计中的应用;学会考虑电磁辐射干扰及传导干扰的电力电子、电子线路的硬件及软件设计方法。
(支撑毕业能力要求2.1)2.在教学过程中,以实际工程问题为主线,讲解在电力电子装置及电子线路设计过程中如何考虑电磁兼容问题,重点讲述装置、线路器件的参数计算、选择方法及在电力电子装置、电子线路中作用。
使学生对电磁兼容在实际工程中的应用有独立的设计能力。
(支撑毕业能力要求3.1)3.使学生可以运用解析法及经验法对实际的复杂工程问题进行建模、分析并能够提出解决电力电子装置或电子线路电磁干扰的措施,能够制定出相应的解决方案。
(支撑毕业能力要求4.1)四、教学内容、基本要求与学时分配五、其他教学环节(课外教学环节、要求、目标)无。
电力系统中电磁兼容性问题研究

电力系统中电磁兼容性问题研究在当今高度依赖电力的社会中,电力系统的稳定运行至关重要。
然而,电磁兼容性问题却给电力系统的可靠运行带来了诸多挑战。
电磁兼容性(Electromagnetic Compatibility,简称 EMC)是指设备或系统在其电磁环境中能正常工作且不对该环境中任何事物构成不能承受的电磁骚扰的能力。
在电力系统中,各种电气设备在运行时都会产生电磁能量,这些电磁能量可能会相互干扰,影响设备的正常运行,甚至导致系统故障。
因此,深入研究电力系统中的电磁兼容性问题具有重要的现实意义。
电力系统是一个复杂的网络,包括发电、输电、变电、配电和用电等多个环节。
在这些环节中,存在着各种各样的电磁干扰源。
例如,在发电环节,大型发电机的运行会产生电磁场;在输电环节,高压输电线路的电晕放电会产生电磁噪声;在变电环节,变压器的切换操作会引起暂态电磁干扰;在配电环节,各种电力电子设备的高频开关动作会产生谐波干扰;在用电环节,大量的家用电器和工业设备也会产生电磁骚扰。
这些电磁干扰源会通过传导、辐射和感应等方式传播电磁能量,对电力系统中的其他设备产生影响。
传导干扰是指电磁干扰通过电源线、信号线等导体传播;辐射干扰是指电磁干扰通过空间电磁波的形式传播;感应干扰则是指电磁干扰通过电磁感应的方式在其他设备中产生干扰电压或电流。
电磁兼容性问题对电力系统的影响主要体现在以下几个方面:首先,它可能导致电力设备的误动作。
例如,继电保护装置可能会因为受到电磁干扰而误跳闸,造成不必要的停电事故。
其次,电磁兼容性问题会降低电力设备的性能和可靠性。
长期受到电磁干扰的设备可能会出现老化加速、故障率增加等问题。
再者,电磁干扰还可能影响电力系统的测量和控制精度。
例如,电磁干扰可能会使电能计量装置产生误差,影响电力系统的经济运行。
为了解决电力系统中的电磁兼容性问题,需要采取一系列的措施。
从设备的设计和制造方面来说,应采用电磁兼容设计技术,如合理布局电路、选择合适的电子元件、进行屏蔽和滤波等。
电气类外文翻译

1、外文原文(复印件)A: The Utility Interface with Power Electronic SystemIntroductionWe discussed various powerline disturbances and how power electronic converters can perform as power conditioners and uninterruptible power supplies to prevent these poweline disturbances from disrupting the operation of critical loads such as computers used for controlling important processes, medical equipment, and the like. However, all power electronic converters (including those used to protect critical loads) can add to the inherent powerline disturbances by distorting the utility waveform due to harmonic currents injected into the utility grid and by producing electromagnetic interference, To illustrate the problems due to current harmonics ih in the input current i s of a power electronic load, consider the simple block diagram of Fig. 1-6A-1. Due to the finite (non-zero) internal impedance of the utility source which is simply represented by Ls in Fig. l-6A-1, the voltage waveform at the point of common coupling to the other loads will become distorted, which may cause them to malfunction. In addition to the voltage waveform distortion, some other problems due to the harmonic currents are as follows: additional heating and possibly overvoltages (due to resonance conditions) in the utility's distribution and transmission equipment, errors in metering and malfunction of utility relays, interference with communication and control signals, and so on. In addition to these problems, phase-controlled converters cause notches in the utility voltage waveform and many draw power at a very low displacement power factor which results in a very poor power factor of operation.The foregoing discussion shows that the proliferation of power electronic systems and loads has the potential for significant negative impact on the utilities themselves, as well as on their customers. One approach to minimize this impact is to filter the harmonic currents and the electromagnetic interference (EMI) produced by the power electronic loads. A better alternative, in spite of a small increase in the initial cost, may be to design the power electronic equipment such that the harmoniccurrents and the EMI are prevented or minimized from being generated in the first place. Both, the concerns about the utility interface and the design of power electronic equipment to minimize these concerns are discussed here.Generation of Current HarmonicsIn most power electronic equipment, such as switch-mode dc power supplies, uninterruptible power supplies (UPS), and ac and dc motor drives, ac-to-dc converters are used as the interface with the utility voltage source. Commonly, a line-frequency diode rectifier bridge as shown in Fig.1-6A-2 is used to convert line frequency ac into dc. The rectifier output is a dc voltage whose average magnitude Ud is uncontrolled.A large filter capacitor is used at the rectifier output to reduce the ripple in the dc voltage Ud. The dc voltage Ud and the dc current Id are unipolar and unidirectional, respectively. Therefore, the power flow is always from the utility ac input to the dc side. These line-frequency rectifiers with a falter capacitor at the dc side were discussed in detail in other section.A class of power electronic systems utilizes line-frequency thyristor-controlled ac-to-dc converters as the utility interface. In these converters, which were discussed in detail, the average dc output voltage Ud is controllable in magnitude and polarity, but the dc current Id remains unidirectional. Because of the reversible polarity of the dc voltage, the power flow through these converters is reversible. As was pointed out, the trend is to use these converters only at very high power levels, such as in high-voltage dc transmission systems. Because of the very high power levels, the techniques to ffdter the current harmonics and to improve the power factor of operation are quite different in these converters, as discussed in other section, than those for the line-frequency diode rectifiers.The diode rectifiers are used to interface with both the single-phase and the three-phase utility voltages. Typical ac current waveforms with minimal filtering were shown in other section. Typical harmonics in a single-phase input current waveform are listed in Table 1-6A-1, where the harmonic currents Ih are expressed as a ratio of the fundamental current Il. As is shown by Table 1-6A-l, such current waveformsconsist of large harmonic magnitudes. Therefore, for a finite internal per-phase source impedance Ls, the voltage distortion at the point of common coupling in Fig. 1-6A-1 can be substantial. The higher the internal source inductance Ls, the greater would be the voltage distortion.Current Harmonics and Power FactorAs we discussed in other section, the power factor PF at which an equipment operates is the product of the current ratio Il / Is and the displacement power factor DPF:In Eq. (1-6A-I), the displacement power factor equals the cosine of the angle Φ1. The current ratio Il / Is in Eq. (1-6A-l) is the ratio of the rms value of the fundamental frequency current component to the rms value of the total current. The power factor indicates how effectively the equipment draws power from the utility; at a low power factor of operation for a given voltage and power level, the current drawn by the equipment will be large, thus requiting increased volt-ampere ratings of the utility equipment such as transformers, transmission lines, and generators. The importance of the high power factor has been recognized by residential and office equipment manufacturers for their own benefit to maximize the power available from a wall outlet. For example from a 120V, 15A electrical circuit in a building, the maximum power available is 1.8 kW, provided the power factor is unity. The maximum power that can be drawn without exceeding the 15A limit decreases with decreasing power factor. The foregoing arguments indicate the responsibility and desirability on the part of the equipment manufacturers and users to design power electronic equipment with a high power factor of operation. This requires that the displacement power factor DPF should be high in Eq. (1-6A-I). Moreover, the current harmonics should be low to yield a high current ratio I1 / Is in Eq. (1-6A- 1).B: A Three-phase Pre-converter for Induction HeatingMOSFETBridge InvertersIntroductionHigh frequency power supplies, based on MOSFET bridge inverters, are already widely used for induction heating applications. These units require dc input voltages of about 400V to allow efficient operation of the MOSFETs employed. This supply voltage is usually obtained by using a three-phase rectifier stage, appropriate smoothing components or by employing thyristor phase- angle control to the mains supply. This kind of mains frequency power supply allows output power control of the induction heater, but it suffers from highly distorted input current waveforms with a low power factor. New legislation has been proposed to limit the maximum magnitude of harmonics drawn from the mains supply and different strategies have been suggested to reduce mains pollution.Investigations have been made to replace mains frequency power supplies by switched mode pre-converters. Switched mode converters can be designed to draw sinusoidal input currents thus avoiding the need for large and expensive mains frequency filters. At the same time these converters provide output power control and implementation of a small size high frequency isolation transformer. Power factor corrected three-phase ac-dc switched mode converter systems have usually been obtained using three identical single-phase converters with a common output filter. These systems overcome problems of mains pollution, but suffer from the disadvantage of a relatively large number of components and the need for complicated control and synchronization circuits. To reduce component costs, a structure based on a boost converter with three-phase input diode rectifier has been suggested. However, when operated direct-off-line from a three-phase 415V mains supply, this structure leads to high output voltages above lkV.In this paper, a novel method to achieve power factor correction for three-phase ac to dc power converters is described. The proposed topology is based on the buck converter and allows therefore output voltages to be below the maximum input voltage. The proposed topology utilizes a three- phase diode rectifier at the mains input and a single active switching device. The active switching device operates underzero-current switching conditions, resulting in very high converter efficiencies and low RFI emissions.Zero-current switching technique allows semiconductor devices to be operated at much higher switching frequencies and with reduced drive requirements compared with conventional switched mode operation.The proposed single-ended resonant converter with three-phase diode rectifier offers good opportunities for medium power, ac to dc applications. It combines simplicity and ease of control with high converter efficiency and high output power capabilities. It will be shown in the paper, that these characteristics make the converter very suitable as a direct replacement for the conventional mains frequency power supply used to supply induction heating MOSFET bridge inverters.General DescriptionA block diagram of the proposed induction heating system is shown in Fig. 1-6B-1. Block 1 represents the pre-converter that produces the dc supply voltage to feed to the RF MOSFET bridge inverter. Its output voltage should be controllable over a wide range to control the output power of the inverter and it must be able to operate with a wide range of load resistance to compensate load changes of the induction heating inverter stage. The pre-converter should operate direct-off-line from a three-phase 415V mains supply, drawing sinusoidal input current waveforms with a power factor approaching unity.Block 2 shows the RF MOSFET bridge inverter.The required maximum supply voltage of the MOSFET bridge lies between 300V and 400V. Block 3 represents the control and protection circuit used to stabilise the output power and to allow reliable operation of the induction heater in an industrial environment.Principle of Converter OperationA circuit diagram of the proposed three-phase ac to dc converter topology is shown in Fig. 1- 6B-2. The converter input currents are filtered through the input inductors L1, L2, L3. These inductors are designed so that the converter input currents are approximately constant over a whole switching cycle.During the OFF time of switch S, all three capacitors are charged by the inputcurrents I1, I2,I3. Consequently the three capacitor voltages Uc1, Uc1, Uc1 begin simultaneously to increase at a rate proportional to their respective input currents. If discontinuous operation is assumed the initial voltages of all capacitors C1, C2, C3 are zero when the switch ceases conducting. Hence, the peak voltage across each capacitor at the end of the OFF interval is proportional to their respective phase input current during the same OFF interval. Since capacitor voltages always begin at zero, it means that their average values during OFF time are linearly dependent on the phase input currents.During the ON time of switch S the energy stored in the three input capacitors C1, C2 and C3 is discharged through the six rectifier diodes VD1 –VD6, the switch S and the resonant inductor Lr. The rate of current decrease is dependent on the phase currents I1, I2, I3 and the switch current I0. The average value of the capacitor voltages Uc1, Uc2, Uc3 during the ON time are not linearly dependant on their phase input currents.To draw sinusoidal input currents from the mains supply the converter must draw input currents averaged over each switching cycle which are proportional to the phase voltages. Assuming steady state converter operation, the average phase input voltages over each switching cycle must be equal to the appropriate average input capacitor voltages during the switch OFF time plus the average input capacitor voltages during the switch ON time.Average input capacitor voltages during the switch OFF time have been shown to be proportional to the phase input currents, but during the switch ON time this is not true. However, if the switch ON time of the converter is mucteshorter than the switch OFF time, then the shape of the phase input currents will approach a sinusoidal waveform with unity power factor.2、外文资料翻译译文A:效用界面与电力电子系统介绍我们之前介绍了许多种电力线的干扰情况和电力系统转换器是如何在作为电力调节器和电力电子变换器时,用来防止那些电力线扰动干扰操作的临界荷载,例如电脑用于控制重要步骤,医疗设备,以及类似其他情况。
电磁兼容性(EMC)简介电磁兼容是研究电磁干扰的学科

电磁兼容性(EMC)简介电磁兼容是研究电磁干扰的学科。
电磁干扰是人们早就发现的电磁现象,它几乎和电磁效应的现象同时被发现,1981年英国科学家发表“论干扰”的文章,标志着研究干扰问题的开始。
1989年英国邮电部门研究了通信中的干扰问题,使干扰问题的研究开始走向工程化和产业化。
虽然电磁干扰问题由来已久,但电磁兼容这个新的综合性学科确是近代形成的。
40年代提出电磁兼容性(Electromagnetic Compatibility缩写为EMC)概念,是电磁干扰问题由单纯的排除干扰逐步发展成为从理论上、技术上全面控制用电设备在其电磁环境中正常工作能力保证的系统工程。
70年代以来,电磁兼容技术逐渐成为非常活跃的学科领域之一。
80年代,美国、德国、日本、前苏联、法国等经济发达国家在电磁兼容研究和应用方面达到很高的水平。
建立了相应的电磁兼容标准和规范,电磁兼容设计成为民用电子设备和军用武器装备研制中必须严格遵循的原则和步骤。
电磁兼容性成为产品可靠性保证中的重要组成部分。
90年代,电磁兼容性工程以事后检测处理发展到预先分析评估、预先检验、预先设计。
在我国电磁兼容理论和技术的研究起步较晚,直到80年代之后才组织系统地研究并制定国家级和行业级的电磁兼容性标准和规范。
90年代以来,随着国民经济和高科技产业的形迅速发展,在航空、航天、通信、电子等部门,电磁兼容技术受到格外重视。
电磁兼容性的定义由于电磁干扰源的大量普遍曾在,电磁干扰现象经常发生。
如果在一个系统中各种用电设备能和谐正常工作而不致相互发生电磁干扰造成性能改变和遭受损坏,人们就满意的称这个系统中的用电设备是相互兼容的。
但是随着用电设备功能的多样化、结构的复杂化、功率加大和频率提高,同时它们的灵敏度已越来越高,这种相互包容兼顾、各显其能的状态很难获得。
为了使系统达到电磁兼容,必须以系统的电磁环境为依据,要求每个用电设备不产生超过一定限度的电磁发射,同时又要求它具有一定的抗干扰能力。
电磁兼容管理计划

电磁兼容管理计划(中英文实用版)Title: Electromagnetic Compatibility Management Plan1.IntroductionThis document outlines an Electromagnetic Compatibility (EMC) Management Plan, which is designed to ensure that all electronic devices within a specified environment function properly without interference from one another.The plan aims to identify potential sources of electromagnetic interference (EMI) and implement appropriate measures to mitigate their impact on the performance of electronic equipment.1.引言本文档概述了一个电磁兼容(EMC)管理计划,该计划旨在确保特定环境中的所有电子设备能够正常运行,彼此之间不产生干扰。
该计划旨在识别潜在的电磁干扰(EMI)来源,并采取适当的措施来减轻其对电子设备性能的影响。
2.ScopeThe EMC Management Plan covers all electronic devices, systems, and equipment within a specified area, including but not limited to computers, servers, network devices, telecommunications equipment, and industrial control systems.It also encompasses the development and implementation of policies, procedures, and guidelines to ensure compliance with relevant EMC standards and regulations.2.范围电磁兼容(EMC)管理计划涵盖特定区域内所有电子设备、系统和设备,包括但不限于计算机、服务器、网络设备、电信设备以及工业控制系统。
电气设备中的电磁兼容性问题研究

电气设备中的电磁兼容性问题研究引言:电气设备的使用已经成为我们生活中不可或缺的一部分,而电磁兼容性问题则成为了人们关注的焦点。
电磁兼容性(Electromagnetic Compatibility, EMC)是指电气设备在工作过程中不会产生干扰,同时也不会受到外部电磁场的干扰。
本文将从电磁兼容性的基本概念出发,探讨电气设备中的电磁兼容性问题化解方法和未来发展趋势。
一、电磁兼容性的基本概念电磁兼容性可以分为电磁干扰和电磁耐受两个方面。
电磁干扰是指电气设备产生的电磁信号对其他设备造成的干扰,如电磁辐射干扰、导线电磁辐射干扰等。
电磁耐受则是指电气设备对来自外部电磁场的干扰能力,包括电磁辐射敏感度、导线电磁辐射敏感度等。
电磁兼容性的研究旨在解决电气设备在使用过程中产生的干扰问题以及其对外部电磁场的敏感度问题。
二、电磁兼容性问题与解决方案(一)电磁干扰问题电磁干扰是电气设备中最常见的问题之一,其主要表现为电磁辐射和电磁传导两种形式。
1. 电磁辐射干扰电磁辐射干扰指电气设备产生的电磁辐射对周围其他设备或系统产生的干扰。
电磁辐射干扰问题需要通过设计合理的电路布局、优化电源接口以及采用合适的滤波器等方法来解决。
在电路设计阶段,应考虑到信号线和功率线之间的相互影响,合理布局电路板,减少电磁辐射。
2. 导线电磁辐射干扰导线电磁辐射干扰是由传导方式引起的干扰,主要是由于信号线、电源线和地线等导线之间的电磁耦合引起的。
解决导线电磁辐射干扰的方法包括合理布局导线,减小导线长度,使用合适的滤波器等。
(二)电磁耐受问题电磁耐受问题是指电气设备对外部电磁场的干扰敏感程度。
电磁耐受问题的解决方法主要包括屏蔽、滤波、接地等。
1. 屏蔽屏蔽是解决电磁耐受问题的一种重要方法。
通过在电气设备中采用金属屏蔽材料,可以将外部电磁场的干扰信号屏蔽在设备外部,从而保证设备内部的正常工作。
屏蔽设计方案包括结构屏蔽和材料屏蔽两种。
2. 滤波滤波是另一种解决电磁耐受问题的常用方法。
高压直流电力系统的电磁兼容性

高压直流电力系统的电磁兼容性一 Introduction高压直流(High Voltage Direct Current,HVDC)电力系统是一种在电网传输输电的系统。
它具有传输距离远、输电损耗小、控制灵活等优势。
然而,随着其应用的不断扩大,HVDC系统的电磁兼容性问题逐渐凸显。
二 HVDC系统的电磁兼容性问题1. 互干扰问题HVDC系统由直流输电线路和变换站组成,其中变换站通过变压器、换流器等设备将交流电转换为直流电或直流电转换为交流电。
在这个过程中,可能会产生互相干扰的问题,如交流电网的谐波可能对HVDC系统产生影响,而直流电线路本身也可能干扰到周围的交流电网。
2. 电磁辐射问题HVDC系统中的高压电缆、接线等部件在传输过程中会产生较强的电磁辐射。
这些电磁辐射可能对周围的设备和人员产生影响,如干扰到通信设备、影响到居民的身体健康等。
三提高HVDC系统的电磁兼容性的方法为了解决HVDC系统的电磁兼容性问题,可以采取以下措施:1. 优化系统设计在HVDC系统设计过程中,可以通过合理布置线路、减少电缆的长度、增加屏蔽等方式来降低电磁辐射。
同时,还可以考虑采用低辐射材料和优化电缆绝缘等措施来降低电磁辐射。
2. 均衡系统运行HVDC系统的正常运行对电力稳定和电磁兼容性至关重要。
通过优化电力调整系统、保证系统的均衡运行,可以降低互干扰等问题的发生。
3. 加强屏蔽和隔离合理的屏蔽和隔离可以有效地降低HVDC系统的电磁辐射和互干扰。
可以采用金属屏蔽、电磁辐射防护罩等方式来增强系统的屏蔽效果,同时设置适当的隔离距离和隔离设备,减少互干扰。
4. 进行电磁兼容性测试和评估对构建好的HVDC系统进行电磁兼容性测试和评估,及早发现和解决问题。
可以通过测量电磁辐射水平、检测系统的抗干扰能力等方式来评估系统的电磁兼容性,并根据评估结果进行相应的优化和改进。
四结论随着HVDC系统的广泛应用,提高其电磁兼容性已经成为一个重要的课题。
电子电力系统中的电磁兼容性问题

电子电力系统中的电磁兼容性问题电子电力系统(EES)主要由电力设备和控制设备组成,而这些设备的运作需要使用电磁能量。
但是,电磁能量不仅可以促进设备的良好运作,还可能导致系统崩溃。
因此,电磁兼容性问题在EES中变得非常重要。
电磁兼容性(EMC)是研究电子设备之间电磁相互干扰和耐受性的科学。
干扰产生的原因是设备各自上产生的电磁场。
EMCEMC是一项综合性的科学,涉及到可靠性、安全性、经济性、法规、规范等多个方面。
电磁兼容性主要有两个方面,即辐射和传导。
辐射是指电子设备以电磁波形式向外传播所产生的电磁干扰;传导是指电子设备通过导体互相干扰。
这两个方面可以共同产生电磁干扰。
电磁兼容性问题的影响EES中的电磁干扰不仅会影响到系统的正常运作,还可能会影响到系统的稳定性和安全性。
下面列举一些可能造成电磁干扰的情况:1.辐射来自于通讯设备、雷达、微波炉和无线接收器等电子设备。
2.线路上漂浮的电压会使信号变形,这会产生电磁干扰。
3.过电流和过电压的产生也会导致电磁干扰。
4.电磁干扰将损坏控制器、触摸屏等电子设备,从而影响到系统应用。
影响电磁兼容性的各种因素EES的电磁兼容性极其复杂,数以百计的因素可以影响电磁相互干扰和耐受性。
一些主要因素如下所述:1.由电子设备发射的电磁场。
这是电磁干扰最常见的来源。
2.线路上的电压浮动。
这些浮动产生的电磁场可以超出线路的表面,这就会造成辐射干扰。
3.不同设备之间的接地状况。
接地附近的电磁场可以影响电子设备。
4.在设备之间传递的信号品质。
不良的信号品质可能会导致需要重传或数据丢失等问题。
电磁兼容性解决方案有很多方法和技术可以帮助我们解决EES中的电磁兼容性问题。
下面列举一些可能有效的解决方案:1.使用过滤器。
过滤器可以减少传导和辐射干扰。
2.正确选择设备和线材。
选择电磁兼容性高的设备和线材可以减少电磁干扰和耐受性的问题。
3.增加接地垫。
接地垫可以减少由不同设备间传递的电磁场。
4.优化系统设计。
煤矿电气系统中EMC问题研究与解决方案

电气工程与自动化!Di#nqi Gongcheng yu Zidonghu2煤矿电气系统中EMC问题研究与解决方案庞小光(北京天地华泰矿业管理股份有限公司,北京100013)摘要:对煤矿电气系统中的电磁兼容性(EMC)问题进行了研究,分析了EMC问题对设备的危害和处理措施,结合某典型案例,提出了EMC问题的解决方案,有利于实现电力电子电路系统中电磁兼容的状态。
关键词:煤矿电气系统;EMC问题;解决方案1EMC问题的产生机理和耦合途径1.1产生机理电磁兼容性(Electro Magnetic Compatibility,EMC)是指设备或系统在其电磁环境中按照要求运行且不会对其环境中的任何设备产生电磁的力电子的方提了工业平和自动化程度,方便了人们的生活,方电磁了,对设备造成了[1]o1.2干扰源与耦合途径在电力电子电路系统中,电磁兼容的要有:(1孚在,产生和;(2;(3;(4)电力电子电路方产生的;(5;(6,电路不对[2]合对的路和。
在电路中在电路产生合。
3电子路1产生的电厶在电路Z上产生压降会电子线路2的子处电压。
1.2.1电容耦合在且在不电的在电容合。
于电,在电,电电容C c。
电容C c的小的几何形状以及在一定电下的距决!3"。
1.2.2电合电合生在不电电路或不的闭合电路中。
在闭环中流动的交流电将产生交变磁场。
该交变磁其他闭合电路并产生电。
电合互系数%,互感系数%由闭环的一般形状和电路的距离决。
2EMC问题对设备的危害和处理措施2.1变压器危害:增加铜;增加漏磁;增加铁;增加;增加温升。
处理措施实心、扁平连接机柜的所有构件。
需要注意的是,安装接地是机械的要保护措施。
然而对于动系统,接地和度。
系统可采用星方式接地或每单独接地。
对于动系统说,优先选择所有安装的部都通过其表电气连接或网状接地。
信号电缆和动力电缆必须相互分a避免耦合基金项目:天地华泰技术创新基金资助项目(TDHTKY2017001)),最小距20cm。
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外文资料译文Power Electronics Electromagnetic CompatibilityThe electromagnetic compatibility issues in power electronic systems are essentially the high levels of conducted electromagnetic interference (EMI) noise because of the fast switching actions of the power semiconductor devices. The advent of high-frequency, high-power switching devices resulted in the widespread application of power electronic converters for human productions and livings. The high-power rating and the high-switching frequency of the actions might result in severe conducted EMI. Particularly, with the international and national EMC regulations have become more strictly, modeling and prediction of EMI issues has been an important research topic. By evaluating different methodologies of conducted EMI modeling and prediction for power converter systems includes the following two primary limitations: 1) Due to different applications, some of the existing EMI modeling methods are only valid for specific applications, which results in inadequate generality. 2) Since most EMI studies are based on the qualitative and simplified quantitative models, modeling accuracy of both magnitude and frequency cannot meet the requirement of the full-span EMI quantification studies, which results in worse accuracy. Supported by National Natural Science Foundation of China under Grant 50421703, this dissertation aims to achieve an accurate prediction and a general methodology. Several works including the EMI mechanisms and the EMI quantification computations are developed for power electronic systems. The main contents and originalities in this research can be summarized as follows.I. Investigations on General Circuit Models and EMI Coupling ModesIn order to efficiently analyze and design EMI filter, the conducted EMI noise is traditional decoupled to common-mode (CM) and differential-mode (DM) components. This decoupling is based on the assumption that EMI propagation paths have perfectly balanced and time-invariant circuit structures. In a practical case, power converters usually present inevitable unsymmetrical or time-variant characteristics due to the existence of semiconductor switches. So DM and CM components can not be totally decoupled and they can transform to each other. Therefore, the mode transformation led to another new mode of EMI: mixed-mode EMI. In order to understand fundamental mechanisms by which the mixed-mode EMI noise is excited and coupled, this dissertation proposes the general concept of lumped circuit model for representing the EMI noise mechanism for power electronic converters. The effects of unbalanced noise source impedances on EMI mode transformation are analyzed. The mode transformations between CM and DM components are modeled. The fundamental mechanism of the on-intrinsic EMI is first investigated for a switched mode power supply converter. In discontinuous conduction mode, the DM noise is highly dependent on CM noise because of the unbalanced diode-bridge conduction. It is shown that with the suitable and justified model, many practical filters pertinent to mixed-mode EMI are investigated, and the noise attenuation can also be derived theoretically. These investigations can provide a guideline for full understanding of the EMI mechanism and accuracy modeling in power electronic converters. (Publications: A new technique for modeling and analysis of mixed-mode conducted EMI noise, IEEE Transactions on Power Electronics, 2004; Study of differential-mode EMI of switching power supplies with rectifier front-end, Transactions of China Electrotechnical Society, 2006)II. Identification of Essential Coupling Path Models for Conducted EMI PredictionConducted EMI prediction problem is essentially the problem of EMI noise source modeling and EMI noise propagation path modeling. These modeling methods can be classified into two approaches, mathematics-based method and measurement-based method. The mathematics method is very time-consuming because the circuit models are very complicated. The measurement method is only valid for specific circuit that is conveniently to be measured, and is lack of generality and impracticability. This dissertation proposes a novel modeling concept, called essential coupling path models, derived from a circuit theoretical viewpoint, means that the simplest models contain the dominant noise sources and the dominant noise coupling paths, which can provide a full feature of the EMI generations. Applying the new idea, this work investigates the conducted EMI coupling in an AC/DC half-bridge converter. Three modes of conducted EMI noise are identified by time domain measurements. The lumped circuit models are derived to describe the essential coupling paths based on the identification of the EMI coupling modes. Meanwhile, this study illustrates the extraction of the parameters in the afore-described models by measurements, and demonstrates the significance of each coupling path in producing conducted EMI. It is shown that the proposed method is very effective and accurate in identifying and capturing EMI features. The equivalent models of EMI noise are sorted out by just a few simple measurements. Under these approaches, EMI performance can be predicted together with the filtering strategies. (Publications: Identification of essential coupling path models for conducted EMI prediction in switching power converters, IEEE Transactions on Power Electronics, 2006; Noise source lumped circuit modeling and identification for power converters, IEEE Transactions on Industrial Electronics, 2006)III. High Frequency Conducted EMI Source ModelingThe conventional method of EMI prediction is to model the current or voltage source as a periodic trapezoidal pulse train. However, the single slope approximation for rise and fall transitions can not characterize the real switching transitions involved in high frequency resonances. In most common noise source models simple trapezoidal waveforms are used where the high frequency information of the EMI spectrum is lost. Those models made several important assumptions which greatly impair accuracy in the high frequency range of conducted noise. To achieve reasonable accuracy for EMI modeling at higher frequencies, the relationship between the switching transitions modeling and the EMI spectrum is studied. An important criterion is deduced to give the reasonable modeling frequency range for the traditional simple approximation method. For the first time, an improved and simplified EMI source modeling method based on multiple slope approximation of device switching transitions is presented. To confirm the proposed method, a buck circuit prototype using an IGBT module is implemented. Compared with the superimposed envelops of the measured spectra, it can be seen that the effective modeling frequency is extended to more than 10 MHz, which verifies that the proposed multiple slopes switching waveform approximation method can be applied for full-span EMI noise quantification studies. (Publications: Multiple slope switching waveform approximation to improve conducted EMI spectral analysis of power converters, IEEE Transactions on Electromagnetic Compatibility, 2006; Power converter EMI analysis including IGBT nonlinear switching transient model, IEEE Transactions on Industrial Electronics, 2006)IV. Loop Coupling EMI Modeling in Power Electronic SystemsPractical examples of power electronic systems that have various electrical, electromechanical andelectronics apparatus emit electromagnetic energy in the course of their normal operations. In order to predict the EMI noise in a system level, it is significant to model the EMI propagation characteristics through electromagnetic coupling between two apparatus circuit within a power electronic system. The PEEC modeling technique which was first introduced in 1970s has recently becomes a popular choice in relation to the electromagnetic analysis and EMI coupling. In previous studies, the integral equation based method was mostly applied in the electrical modeling and analysis of the interconnect structure in very large scale integration systems, only at the electronic chip and package level. By introducing the partial inductance theory of PEEC modeling technique, this work investigates the EMI loop coupling issues in power electronic circuits. The work models the magnetic flux coupling due to EMI current on one conductor and another by mutual inductance. To model the EMI coupling between the grounding circuits, this study divides the ground impedance into two parts: one is the internal impedance and the other is the external inductance. The external inductance due to the fields external to the rectangular grounding loop and flat conductor is modeled. To verify the mathematical models, the steel plane grounding test configurations are constructed and the DM and CM EMI coupling generation and modeling technique are experimentally studied. The comparison between the measured and calculated EMI noise voltage validates the proposed analysis and models. These investigations and results can provide a powerful engineering application of analyzing and solving the coupling EMI issues in power electronic circuits and systems. (This part of work is one of the main contributions of the awarded project of Military Science and Technology Award in 2006, where the author is No. 4 position. Publication: Loop coupled EMI analysis based on partial inductance models, Proceedings of the Chinese Society of Electrical Engineering, 2007)V. Conducted EMI Prediction for PWM Conversion UnitsPWM-based power conversion units are the main EMI noise sources in power systems. Due to the various PWM strategies and the large number of switches, a common analytical approach for the PWM-based switched converter systems has not been dated. Determination of the frequency spectrum of a PWM converter is quite complex and is often done by using an FFT analysis of a simulated time-varying switched waveform. This approach requires considerable computing capacity and always leaves the uncertainty as to whether a subtle simulation round-off or error may have slightly tarnished the results obtained. By introducing the principle of the double Fourier integral, this work presents a general method for modeling the conduced EMI sources of PWM conversion units by identifying double integral Fourier form to suit each PWM modulation. Appling the proposed method, three PWM strategies have been discussed. The effects of different modulation schemes on EMI spectrum are evaluated. The EMI modeling and prediction efforts from an industrial application system are studied comprehensively. Comparison between the measured and the predicted spectrum confirms the validity of the EMI modeling and prediction method. This method breaks through the limitations of time-consuming and considerable accumulated error by traditional time-domain simulations. A standard without relying on simulation but a common analytical approach has been obtained. Clearly, it can be regarded as a common analytical approach that would be useful to be able to model and predict the exact EMI performance of the PWM-based power electronic systems. (Publications: DM and CM EMI Sources Modeling for Inverters Considering the PWM Strategies, Transactions of China Electrotechnical Society, 2007. High Frequency Model of Conducted EMI for PWM Variable-speed Drive Systems, Proceedings of the Chinese Society of Electrical Engineering,2008)电力电子系统的电磁兼容问题电力电子系统的电磁兼容问题,集中体现为半导体器件的开关工作方式产生的传导性电磁干扰(EMI)。