一种适用于风电外送的混合高压直流输电系统  

A KIND OF HYBRID HVDC TRANSMISSION SYSTEM SUITABLE FOR WIND POWER CONNECTION

作　　者：韩平平[1] 陈凌琦 丁明[1] 张炎[1] 李宾宾 Han Pingping;Chen Lingqi;Ding Ming;Zhang Yan;Li Binbin(New Energy Utilization and Energy Saving Laboratory,Hefei University of Technology,Hefei 230009,China;State Grid Electric Power Research Institute of Anhui, Hefei 230601,China)

机构地区：[1]安徽省新能源利用与节能重点实验室,合肥工业大学,合肥230009 [2]国网安徽电力科学研究院,合肥230601

出　　处：《太阳能学报》2019年第8期2162-2169,共8页Acta Energiae Solaris Sinica

基　　金：国家重点研发计划(2016YFB0900601)

摘　　要：整流侧采用模块化多电平换流器(MMC),逆变侧采用电网换相换流器(LCC)的混合高压直流输电系统可结合两者的优点,是一种适用于风电外送的新型拓扑。为弥补MMC无法清除直流侧故障的缺陷,可在整流侧直流线路上装设混合式高压直流断路器。针对单级接地和双极短路2种故障分析其故障特性和对系统的影响,并根据故障电流特性设计断路器时序控制策略。基于PSCAD仿真软件建立该输电模型并仿真分析其在稳定送端交流母线电压上的优势,然后验证所提故障特性分析,最后证明所设计的时序控制策略可有效清除直流侧故障。A hybrid high voltage direct current system can combine the merits of both MMC and LCC,in which the rectifier side is made up of the modular multilevel converter(MMC)and the inverter side is composed of the line commutated converter(LCC). It is a new type of topology suitable for wind power transmission. The hybrid HVDC breaker is installed on the DC transmission line of the rectifier side to block the fault current paths which could remedy the limitation that the MMC is unable to clean up DC side faults. The DC-link fault characteristics of line-to-ground and line-to-line,as well as their effects on system are analyzed,and time sequence control strategy based on current characteristics is designed. A hybrid HVDC simulation system is built based on PSCAD softuware,and the advantage on stabilizing the voltage of converter side AC bus is simulated and analyzed. Moreover,the fault characteristics proposed is validated. Finally,Simulation results verify the time sequence control can effectively isolate the DC side fault.

关 键 词：高压直流输电 风力发电 故障电流 模块化多电平换流器 混合式高压直流断路器 

分 类 号：TM723[电气工程—电力系统及自动化] TM614