高压直流输电系统抑制连续换相失败的策略研究  

Research on the strategy of mitigate consecutive commutation failure for HVDC transmission system

作　　者：赵晓龙 陈卓[1] 田霄 何青龙 张叶贵 Zhao Xiaolong;Chen Zhuo;Tian Xiao;He Qinglong;Zhang Yegui(School of Electrical Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学电气工程学院,贵阳550025

出　　处：《电测与仪表》2022年第4期185-190,共6页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金资助项目(51567005)。

摘　　要：对于直流馈入受端电网,换相失败是一种最常见的故障。为减少输电系统发生连续换相失败的概率,对换相机理和控制环节的运行逻辑进行分析,然后结合低压限流控制器的特点,提出了一种可以抑制连续换相失败的策略。通过预测模块提前减小逆变触发角,增大换相裕度,同时在整流侧补偿触发角,抑制直流电流上升,并且利用交流母线电压波动小的特点,代替低压限流装置的启动电压。基于PSCAD/EMTDC平台,使用CIGRE标准模型测试所提出的方法。通过仿真实验可知,所用的控制策略在逆变侧发生交流系统短路故障时,能有效抑制系统的连续换相失败,并且会改善故障恢复特性。Commutation failure is one of the most common faults for high voltage direct current(HVDC)receiving end power grid.In order to reduce the probability of continuous commutation failure in HVDC power transmission system,the mechanism of commutation failure and the action logic of HVDC system control link is analyzed.Then,combing with the characteristic of voltage dependent current order limiter(VDCOL)controller which is widely used in HVDC,a novel control strategy is proposed to suppress continuous commutation failure.Predictive module will reduce the inverter trigger angle and increase commutation margin in advance,meanwhile,the rectifying side will compensate for the trigger angle to restrain DC current rise.And then,the AC bus voltage substitutes the starting voltage of VDCOL for its small fluctuation.Based on the CIGRE benchmark model of HVDC,the proposed method is tested in PSCAD/EMTDC.The simulation results show that the proposed method can suppress continuous failure during short circuit fault occurs in AC system,which improves the fault recovery performance effectively.

关 键 词：高压直流输电 连续换相失败 低压限流 CIGRE标准模型 故障恢复 

分 类 号：TM721[电气工程—电力系统及自动化]