高压直流输电简介

沧州师范学院
专业外语阅读
文献综述
系部机械与电气工程学院
姓名李楠
学号1314216113
专业电气工程及其自动化
班级2013级1班
2016年 1 月
高压直流输电简介
摘要:高压直流输电技术被用于通过架空线和海底电缆远距离输送电能；同时在一些不适于用传统交流联接的场合，它也被用于独立电力系统间的联接。

高压直流输电用于远距离或超远距离输电，因为它相对传统的交流输电更经济。

自上世纪80年代以来，电力传输技术的发展步伐明显加快，提高传输能力的办法不断涌现，既有直流输电技术、柔性交流输电技术、分频输电技术等高新技术，同时也有对现有高压交流输电线路的增容改造技术，如升压改造、复导增容改造、交流输电线路改为直流输电技术等。

关键词:高压直流输电技术；经济性；节能
一、介绍
高压直流输电技术被用于通过架空线和海底电缆远距离输送电能；同时在一些不适于用传统交流联接的场合，它也被用于独立电力系统间的联接。

世界上第一条商业化的高压直流输电线路1954年诞生于瑞典，用于连接瑞典本土和哥特兰岛，由阿西亚公司(ASEA, 今ABB集团)完成。

二、功能
在一个高压直流输电系统中，电能从三相交流电网的一点导出，在换流站转换成直流，通过架空线或电缆传送到接受点；直流在另一侧换流站转化成交流后，再进入接收方的交流电网。

直流输电的额定功率通常大于100兆瓦，许多在1000-3000兆瓦之间。

高压直流输电用于远距离或超远距离输电，因为它相对传统的交流输电更经济。

应用高压直流输电系统，电能等级和方向均能得到快速精确的控制，这种性能可提高它所连接的交流电网性能和效率，直流输电系统已经被普遍应用。

高压直流输电是将三相交流电通过换流站整流变成直流电，然后通过直流输电线路送往另一个换流站逆变成三相交流电的输电方式。

它基本上由两个换流站和直流输电线组成，两个换流站与两端的交流系统相连接。

直流输电线造价低于交流输电线路但换流站造价却比交流变电站高得多。

一般认为架空线路超过600-800km，电缆线路超过40-60km直流输电较交流输电经济。

随着高电压大容量可控硅及控制保护技术的发展，换流设备造价逐渐降低直流输电近年来发展较快。

我国葛洲坝一上海1100km、±500kV，输送容量的直流输电工程，已经建成并投入运行。

此外，全长超过2000公里的向家坝-上海直流输电工程也已经完成，予2010年7月8日投入运行。

该线路是目前（截至2011年初）世界上距离最长的高压直流输电项目。

三、节能探索编辑
自上世纪80年代以来，电力传输技术的发展步伐明显加快，提高传输能力
的办法不断涌现，既有直流输电技术、柔性交流输电技术、分频输电技术等高新技术，同时也有对现有高压交流输电线路的增容改造技术，如升压改造、复导增容改造、交流输电线路改为直流输电技术等。

直流输电，对于提高现有传输系统的传输能力，挖掘现有设备潜力，具有十分重要的现实意义，实施起来可收到事半功倍的效果。

（一）经济性三大特性突出节能效果
从经济方面看，直流输电有以下三个主要优点：
首先，线路造价低，节省电缆费用。

直流输电只需两根导线，采用大地或海水作回路只用一根导线，能够节省大量线路投资，因此电缆费用省得多。

其次，运行电能损耗小，传输节能效果显著。

直流输电导线根数少，电阻发热损耗小，没有感抗和容抗的无功损耗，且传输功率的增加使单位损耗降低，大大提高了电力传输中的节能效果。

最后，线路走廊窄，征地费省。

以同级500千伏电压为例，直流线路走廊宽仅40米，对于数百千米或数千千米的输电线路来说，其节约的土地量是很可观的。

除了经济性，直流输电的技术性也可圈可点。

直流输电调节速度快，运行可靠。

在正常情况下能保证稳定输出，在事故情况下可实现紧急支援，因为直流输电可通过可控硅换流器快速调整功率、实现潮流翻转。

此外，直流输电线路无电容充电电流，电压分布平稳，负载大小不发生电压异常不需并联电抗。

（二）提升空间大功率电力电子器件将改善直流输电性能
直流输电最核心的技术集中于换流站设备，换流站实现了直流输电工程中直流和交流相互能量转换，除在交流场具有交流变电站相同的设备外，还有以下特有设备：换流阀、控制保护系统、换流变压器、交流滤波器和无功补偿设备、直流滤波器、平波电抗器以及直流场设备，而换流阀是换流站中的核心设备，其主要功能是进行交直流转换，从最初的汞弧阀发展到现在的电控和光控晶闸管阀。

晶闸管用于高压直流输电已有很长的历史。

近10多年来，可关断的晶闸管、绝缘门极双极性三极管等大功率电子器件的开断能力不断提高，新的大功率电力电子器件的研究开发和应用，将进一步改善新一代的直流输电性能、大幅度简化设备、减少换流站的占地、降低造价。

参考文献
[1] 向家坝-上海±800kV特高压直流输电示范工程简介．中国电力企业联合会．2011-12-27
[2] ABB参与建造全球最长的高压直流输电线路
Introduction of high voltage direct current
Abstract: High voltage direct current transmission technology is used to transmit electric energy through overhead lines and submarine cable. At the same time, it can be used in the connection between independent power system. High voltage direct current transmission technology has been developed, which has been developed, such as DC transmission technology, flexible AC transmission technology, frequency dividing transmission technology and so on. Made, the complex conductivity of the capacity of the transformation, the AC transmission line to the DC transmission technology.
Key words: High V oltage Direct Current Transmission Technology; Economy; Energy Saving
1.Introduction
HVDC technology is used by overhead lines and submarine cables to long-distance transmission of electricity; at the same time in connection with some not suitable for traditional communication occasions, it has also been used to join the independent power system. The world's first commercial HVDC transmission line in 1954 was born in Sweden, Sweden used to connect local and Gotland and by ASEA (ASEA, the ABB group).
2.Function
In a HVDC system, the electric power from a derived three-phase AC power grid, in the converter is converted into DC, through overhead line or cable is transmitted to the receiving point; on the other side of the converter DC into AC, AC power into DC transmission receiver. The rated power is generally greater than 100 MW, many in the 1000-3000 MW.
High voltage direct current transmission is used for long distance or over - distance transmission, because it is more economical than the traditional AC transmission
High voltage direct current transmission system, power level and direction can be quickly and accurately controlled, this kind of performance can improve the performance and efficiency of AC power grid connected by it, and direct current transmission system has been widely used.
HVDC transmission is three-phase AC converter will through rectifier into DC, and then through the DC transmission lines to another transmission mode into the AC inverter three-phase converter. It basically consists of two converter stations and DC transmission line, AC system two converter stations and both ends of the link.
DC transmission cost is lower than the AC transmission line but the cost is much higher than the converter station AC substation. The general overhead lines that more than 600-800km, more than 40-60km HVDC cable line is AC power economy. With the high voltage and large capacity thyristor control and protection technology development, commutation equipment cost gradually reduce DC transmission in recent years has developed rapidly. In Gezhouba Dam, a Shanghai 1100km, + 500kV, HVDC transmission capacity, has been completed and put into operation. In addition, a total length of more than 2000 kilometers of the Xiangjiaba Shanghai HVDC project has been completed, to 20 10 years into operation in July 8th, the line is currently (as of the beginning of 2011) the world's longest high voltage DC transmission project. 3.Energy saving exploration edito
Since the last century 80's, the development of electric power transmission technology has been improved, and the method of improving transmission capacity has emerged. It has high and new technology, such as DC transmission technology, flexible AC transmission technology, frequency dividing transmission technology and other high technology.
(1)three economic characteristics of the outstanding energy-saving effect
From the economic perspective, the DC transmission has the following three major advantages:
The first line of low cost, saving the cost of cable. The DC transmission only two wires, by land or sea water as a loop of wire line, can save a lot of investment, so the cost of cable so much.
Secondly, the operation of power transmission loss, energy-saving effect is remarkable. The DC transmission line less root number, heat resistance loss, reactive power loss is not inductive and capacity, and increase the transmission power of the unit loss is reduced, greatly improving the energy saving effect of power transmission.
Finally, a narrow corridor, to the land acquisition costs. 500 thousand volt DC line as an example, the corridor is only 40 meters wide, transmission line for hundreds of kilometers or several thousand meters, saving the amount of land is very considerable.
In addition to the economic, technology also has much of the DC transmission. DC speed regulation, reliable operation to ensure stable output. Under normal circumstances, in the case of accident can implement emergency support, because the HVDC converter can quickly adjust the power through the silicon controlled change,
the trend reversed. In addition, DC transmission line the capacitor charging current, voltage distribution stable, load size had no abnormal voltage without parallel reactance.
(2)improving the space high power electronic devices will improve the performance of the DC transmission
The core of the DC transmission technology in converter station equipment, converter realizes the DC transmission project of DC and AC power conversion equipment in addition to each other, have the same AC Substation in communication field, and the following special equipment: valve, control system, converter transformer, AC filter and reactive power compensation equipment, DC filter the flat wave reactor, and DC equipment, while the converter valve is the core equipment in converter station, its main function is AC-DC conversion, from the initial development to the current mercury arc valve control and thyristor valve.
Thyristor for high voltage DC transmission has a long history. Over the past 10 years, can shut off the thyristor, insulated gate bipolar transistors and other high power electronic devices off the ability to continuously improve the development and application of new power electronic devices, will further improve the DC transmission a new generation of performance, greatly simplifying the equipment, reducing the station area, reduce the cost.
Reference
[1] Xiangjiaba - Shanghai 800kV UHVDC transmission demonstration project. China Federation of electric power enterprises.2011-12-27
[2] ABB is involved in the construction of the world's longest high-voltage direct current transmission line.。