VSC直流侧故障限流方案及其特性分析  

Analysis of a Fault Current Limiting Scheme for VSC DC Side Fault

作　　者：狄雅 张金华 钱阳 DI Ya;ZHANG Jinhua;QIAN Yang(School of Electric Power Engineering,Nanjing Institute of Technology,Nanjing 211167,Jiangsu,China)

机构地区：[1]南京工程学院电力工程学院,江苏南京211167

出　　处：《电气传动》2025年第2期77-81,共5页Electric Drive

基　　金：国家自然科学基金(52107098);南京工程学院引进人才科研启动基金(YKJ201965)。

摘　　要：直流配电网中,电压源型换流器(VSC)直流侧线路发生严重金属性短路故障时,故障电流具有上升速度快、峰值大的特点,搭配直流断路器隔离故障时,大大增加了对直流断路器速动性和开断能力的要求。基于VSC双极短路故障特征,提出了在直流线路中串入剩余电流动作保护器(RCD)电流峰值抑制电路的故障限流方案,该限流电路通过控制晶闸管的开断不仅可以截断直流侧电容向故障点的放电回路,还可以有效降低故障电流峰值,并能限制故障稳态电流为给定参考值。利用PSCAD/EMTDC仿真平台对VSC双极短路故障及所提限流方案进行仿真测试,并与其他两种故障限流方案的效果进行比较,验证了所提基于RCD电流峰值抑制电路这一故障限流方案的优越性。In DC power grid,when serious metallic short circuit fault occurs in the DC side line of voltage source converter(VSC),the fault current has the characteristics of a fast rising speed and a large peak.The DC circuit breaker is used to isolate the fault,which greatly increases the requirements for the quick action and breaking capacity of the DC circuit breaker.Based on the VSC bipolar short circuit fault characteristics,a fault current limiting scheme with residual current operated protective device(RCD)current peak suppression circuit in series with the DC line was proposed.The current limiting circuit,which controlled the opening and closing of the thyristor,not only interrupted the discharge loop of the DC side capacitor to the fault point,but also effectively reduced the peak fault current and limited the fault steady state current to a given reference value.The PSCAD/EMTDC simulation platform was used to test the VSC bipolar short circuit fault and the proposed current limiting scheme,and the effectiveness of the proposed scheme was compared with that of the other two fault current limiting schemes,which verified the superiority of the proposed scheme based on energy transfer circuit.

关 键 词：电压源型换流器 故障限流 剩余电流动作保护器电流峰值抑制电路 

分 类 号：TM744[电气工程—电力系统及自动化]