基于无变压器型电压源换流器的柔性多状态开关零序抑制策略  

Zero-sequence Suppression Strategy of Flexible Multi-state Switch Based on Transformerless Voltage Source Converter

作　　者：许烽 陆翌 黄晓明 陆承宇 裘鹏 XU Feng;LU Yi;HUANG Xiaoming;LU Chengyu;QIU Peng(State Grid Zhejiang Electric Power Research Institute,Hangzhou 310014,China)

机构地区：[1]国网浙江省电力有限公司电力科学研究院,浙江省杭州市310014

出　　处：《电力系统自动化》2023年第14期124-129,共6页Automation of Electric Power Systems

基　　金：国家重点研发计划资助项目(2017YFB0903100)。

摘　　要：无变压器型柔性多状态开关(FMS)具有设备紧凑化、高效化等特点,但由于缺少隔离变压器,存在故障后供区间的零序分量交互传递叠加、相互影响等问题。文中首先对无变压器型两电平电压源换流器(VSC)的回路特性进行了分析,并在此基础上利用对称分量法建立了正序、负序和零序系统,揭示了交直流系统间零序分量传递的原因和关键要素。然后,基于理论分析结果,从直流波动抑制和交流零序抑制两方面入手,提出了故障端和非故障端VSC的两种零序抑制策略。最后,在PSCAD/EMTDC内建立了一个两端背靠背型FMS仿真模型,仿真结果验证了理论分析的正确性,以及两种零序抑制策略的有效性。The transformerless flexible multi-state switch(FMS)has the characteristics of compactness and high efficiency.But due to the lack of an isolation transformer,it has problems such as the interactive transmission and superposition of zero-sequence components between different supply areas after a fault.Based on the circuit characteristic analysis of the transformerless two-level voltage source converter(VSC),this paper establishes the positive-sequence,negative-sequence and zero-sequence systems by using the symmetrical component method,which reveals the reasons and key elements of the transmission of zero-sequence components between AC and DC systems.Based on the theoretical analysis results,two zero-sequence suppression strategies of VSC at the fault and non-fault ends are proposed from the two aspects of DC fluctuation suppression and AC zero-sequence suppression.Finally,a two-terminal back-to-back FMS simulation model is established in PSCAD/EMTDC.The simulation results verify the correctness of the theoretical analysis and the effectiveness of the two zero-sequence suppression strategies.

关 键 词：直流配电网 柔性多状态开关 电压源换流器 零序抑制 零序分量 对称分量法 

分 类 号：TM46[电气工程—电器]