特高压直流输电系统交流滤波器电容元件击穿故障仿真研究  

Study on Breakdown Fault Simulation for Capacitor Element of AC Filter of UHVDC Transmission System

作　　者：杨勇 张静 杨智 赵琳 蒋鹏 邹晓峰 陆晓峰 YANG Yong;ZHANG Jing;YANG Zhi;ZHAO Lin;JIANG Peng;ZOU Xiaofeng;LU Xiaofeng(State Gird Zhejiang Electric Power Research Institute,Hangzhou 310014,China;State Gird Zhejiang Electric Power Training Center,Hangzhou 310016,China)

机构地区：[1]国网浙江省电力公司电力科学研究院,杭州310014 [2]国网浙江省电力公司培训中心,杭州310016

出　　处：《电力电容器与无功补偿》2018年第4期1-6,共6页Power Capacitor & Reactive Power Compensation

摘　　要：特高压直流输电系统交流滤波器用作滤除换流装置产生的谐波,并补偿换流装置运行中吸收的无功功率。为了确保交流滤波器的安全可靠运行,通常对交流滤波器配置高压电容器不平衡保护。基于交流滤波器电容器不平衡保护原理,推导了不平衡保护定值的计算公式;根据某特高压直流输电线路工程设备参数,在PSCAD/EMTDC搭建了仿真模型,研究了交流滤波器电容器组元件击穿故障后元件过电压、不平衡电流及流过滤波器总电流等特征量。在内熔丝有效切除故障元件的前提下,理论分析和仿真计算都表明高压电容器不平衡电流与流过交流滤波器总电流比值K随着故障元件个数的增加而增加,且两者计算结果一致。最后,结合一起特高压直流输电工程交流滤波器投切故障,对仿真分析和电容器击穿的故障记录进行对比分析。结果表明:现场故障记录数据分析得到的K值与仿真分析的结果一致,进一步证明了仿真模型的有效性。AC filter for UHVDC transmission system is used to filter harmonic generated by the converter and to compensate the reactive power of the converter which is absorbed during the operation. For assuring safe and reliable operation of AC filter, it is usually equipped with unbalance protection of high voltage capacitors. Based on the unbalance protection principle of high voltage filter capacitor, the calculation formula of unbalance protection setting is derived. The simulation model in PSCAD/EMTDC is set up in accordance with parameters of equipment for certain UHVDC transmission project,such characteristic as overvoltage, unbalance current and total current flowing through filter of the elements of filter capacitor after breakdown is studied. On the premise of effectively clearing faulty element of inner fuse,it is shown by both theoretical analysis and simulation calculation that the ratio K of unbalance current of HV capacitor to the total current of AC filter increases with the increase of element numbers and the calculation of both is in agreement. Finally,the simulation analysis and the breakdown fault record of the capacitor is compared and analyzed with combination of AC filter switching fault of UHVDC transmission project. It is shown by the result that the value K obtained from analysis of site fault record and the analysis result is in agreement,which proves further the effectiveness of the simulation model.

关 键 词：特高压直流输电系统 交流滤波器 不平衡保护 仿真模型 故障记录 

分 类 号：TM721.1[电气工程—电力系统及自动化]