特高压直流输电系统换流站内部故障电磁暂态响应特性及控制策略  

Electromagnetic Transient Response Characteristics of Internal Faults in UHVDC Converter Station and Corresponding Control Strategy

作　　者：董曼玲[1] 黎小林 何俊佳[1] 张丹丹[1] 黄莹 蔡宗远 谢施君[1] 

机构地区：[1]华中科技大学电气与电子工程学院,湖北省武汉市430074 [2]南方电网技术研究中心,广东省广州市510623

出　　处：《电网技术》2010年第3期5-10,共6页Power System Technology

基　　金："十一五"国家科技支撑计划重大项目(2006BAA02A21)~~

摘　　要：以云广±800kV直流输电系统为例,基于PSCAD/EMTDC搭建仿真模型,研究换流站内部阀误开通和不开通2种故障工况,仿真分析整流站和逆变站内部分别发生阀误开通和不开通故障的情况,并对故障引起的系统电磁暂态过程及相应的控制系统策略进行了深入研究。得出以下结论:1)逆变阀发生误开通故障时,会引起换相失败,同时在极线上会出现过电流。但由于一般不会连续发生误开通故障,因而不会出现振荡过电流和过电压;2)整流阀发生误开通故障的可能性比较小,即使开通也仅是提前开通,因此对直流系统的影响比较小;3)逆变侧发生连续不开通故障比整流侧发生连续不开通故障所引起的直流电流振荡幅值大,同时引起的中性线过电压及对负极的影响也大;4)双极运行时,一极发生连续不开通或发生单次误开通,会对另一极运行有影响,引起较小波动。但是该健全极仍可运行,传输一半的功率;5)当故障引起直流电流、电压较大振荡时,整流侧控制系统通过定电流控制与αmin之间的切换来实现系统快速恢复,逆变侧则通过定关断角控制和定电流控制之间的相互切换,使系统快速恢复正常。Taking ±800 kV DC power transmission project from Yunnan to Guangdong for example, based on PSCAD/ EMTDC a simulation model is built to research operation modes of converter station under＇ internal faults of mis-conducting and non-conducting, and simulate the conditions that mis-conducting and non-conducting faults occur inside rectifier station and converter station respectively, and the electromagnetic transient process of DC transmission system and corresponding control strategies are research in depth. Research results are as following： the mis-conduction of inverter will cause commutation failure, however, because in general the mis-conducting fault will not recur, so the over-voltage and over-current due to oscillation will not appear; there is less possibility of mis-conducting fault of rectifier, so its affect on DC transmission system is slight; the non- conducting fault occurred in inverter side one after another will cause higher amplitude of current oscillation than that caused by the same fault occurred in rectifier side, and the caused over-voltage of neutral line will make an evident affect on negative pole; during the bipolar operation, when single-time non-conducting of a pole occurs or non-conducting of a pole occur one after another will affect on the operation of the another pole and cause narrow fluctuation, however the transmitted power will be reduced by half; when the mis-conducting or non.conducting faults lead to stronger oscillation of DC voltage and current, at rectifier side by means of the switchings between constant current control and minimum amin the system can be quickly recovered, and at inverter side by means of the switchings between constant extinguish angle the system can be returned to normal condition.

关 键 词：特高压直流输电 换流站内部故障 误开通 不开通 控制策略 

分 类 号：TM723[电气工程—电力系统及自动化]