高压直流输电技术现状及发展前景

为满足国内直流输电工程的建设需要,紧跟直流输电设备制造水平的前沿技术,对直流输电技术发展的最新成果进行了总结。总结了特高压直流运行方式的特点,指出将电流自然换相技术与柔性直流技术相结合构成多端直流输电技术是未来直流输电技术的发展方向;介绍了多换流站共用接地极技术、换相直流输电技术、大功率半导体器件及换流变压器的应用现状;分析了3种光电式电流互感器的特点;总结了直流输电控制保护系统的发展现状;最后结合生产实际,阐述了跨区电网运行中采用区域直流集控技术的优势。

Recent Advances in High-Voltage Direct-Current Power Transmission and Its Developing Potential

To meet the demands of the construction of high-voltage direct-current(HVDC) power transmission in China and closely follow the most frontier technologies used in the manufacture of HVDC power transmission equipments,the up-to-date achievements in the development of HVDC power transmission technology are summarized.In this paper,the features of operational modes of UHVDC power transmission are presented in suammary;the develoment trend of voltage source converter(VSC) technology is described;and it is pointed out that the multi-terminal HVDC power transmission,which integrates the current natural commutation technology with flexible HVDC power transmission technology,will be the development trend of HVDC power transmission in the future.The HVDC power transmission technology utilizing capacitor commutated converters(CCC) and the common ground electrode technology as well as the technologies of converter transformers and converter valves are presented.Three technical lines for the development of optical-fiber current transformer(CT) are summarized,and the prospect of applying the full optical CT based on the principle of fiber optic interferometric sensor in HVDC power transmission is affirmed.The present situation of control and protective system utilized in HVDC power transmission summed up.Based on the operation experience,the technical and managerial dominant positions of adopting regional centralized monitoring and controlling systems(CMCS) in converter substations are expounded.