直流侧故障下MMC-HVDC输电线路过电压计算  

Overvoltage Calculation of MMC-HVDC Transmission Line under DC Faults

作　　者：潘武略[1] 裘愉涛[1] 张哲任[2] 宣羿 徐政[2] 

机构地区：[1]浙江省电力公司,杭州市310007 [2]浙江大学电气工程学院,杭州市310027

出　　处：《电力建设》2014年第3期18-23,共6页Electric Power Construction

摘　　要：针对基于模块化多电平换流器的高压直流(modular multi-level converter-high voltage direct current,MMCHVDC)输电系统,为了快速而有效地计算其直流侧单极接地故障下直流线路最大过电压,详细地分析了几种相应的等效计算模型。首先,基于能量守恒定律,得到模块化多电平换流器(modular multi-level converter,MMC)的等效模型I。在该模型中,MMC被拆分为直流侧等效电路和交流侧等效电路,其中前者由2个受控电流源和1个理想电容组成。其次,考虑到单极接地故障下MMC子模块电容电压几乎不变的特性,并且直流电缆可以使用π等效电路模型替代,就能得到MMC的等效模型II。最后,基于时域仿真软件PSCAD/EMTDC搭建了400 MW/±200 kV数字仿真模型,验证了2种等效模型的有效性。： In order to quickly and efficiently calculated the maximum overvoltage of DC transmission line in MMC- HVDC （modular multi-level converter-high voltage direct current） transmission system under DC-side single-pole grounding fault, this paper detailed analyzed several corresponding equivalent calculation models. Firstly, the equivalent model I of MMC was built based on the law of conservation of energy, in which the MMC was split into AC-side equivalent circuit and DC-side equivalent circuit, and the former was composed of 2 controlled current sources and an ideal capacitor. Secondly, the equivalent model II of MMC was built with the consideration that the capacitor voltage of sub-module in MMC was almost unchanged under single-pole grounding fault and the DC transmission lines could be replaced by equivalent circuit model. Finally, a 400 MW/± 200 kV digital simulation model was built based on the time-domain simulation software PSCAD/EMTDC, and verified the effectiveness of the 2 kinds of equivalent models.

关 键 词：模块化多电平换流器(MMC)) 高压直流输电 直流侧单极接地故障 过电压计算 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM86