高压直流系统改进型最小换相裕度控制策略  

Improved AMIN control strategy of HVDC system

作　　者：肖建民[1] 宋胜利 卢亚军 张云晓 邹强[1] 王俊生[1] XIAO Jianmin;SONG Shengli;LU Yajun;ZHANG Yunxiao;ZOU Qiang;WANG Junsheng(NR Electric Co.,Ltd.,Nanjing 211102,China;State Grid Corporation of China,Beijing 100031,China;State Grid Economic and Technological Research Institute Co.,Ltd.,Beijing 102209,China)

机构地区：[1]南京南瑞继保电气有限公司,江苏南京211102 [2]国家电网有限公司,北京100031 [3]国网经济技术研究院有限公司,北京102209

出　　处：《电力工程技术》2020年第6期82-88,共7页Electric Power Engineering Technology

基　　金：国家电网有限公司科技项目“提升LCC直流输电系统鲁棒性主动抑制换相失败的关键技术研究”(SGJSJY00JCJS1800115)。

摘　　要：高压直流系统直流侧发生单极故障时,故障极会引起非故障极直流电流增大,严重时可能引起非故障极换相失败。在直流电流增大的情况下,现有最小换相裕度(AMIN)控制无法启动紧急触发来避免换相失败。针对现有AMIN控制无法精确计算实时换相裕度面积的问题,文中根据现有策略的理论推导,首先分析其未能达到预期效果的影响因素;然后,根据分析结果提出考虑换相过程中直流电流变化、电气量采样延时补偿及预测控制的改进型AMIN控制策略;最后,基于与实际控制保护程序一致的直流工程PSCAD/EMTDC模型,对提出的改进型策略进行验证。结果表明,改进型策略能有效避免因直流侧单极故障引起的非故障极换相失败。When a unipolar fault occurs on the direct current(DC)side,the DC current of the non-fault pole increases which is caused by the fault pole.In severe cases,commutation failure of the non-fault pole can be caused.When the DC current increases,the existing area-minimum(AMIN)control cannot start an effective emergency trigger at the first time to avoid commutation failure.For the question that the existing strategy cannot accurately calculate real-time commutation margin area,based on theoretical derivation of the existing strategy,the influencing factors that do not achieve the expected effect are analyzed.Then,according to analysis results,improved AMIN control strategy considering DC current change,electric sampling delay compensation and predictive control during commutation is proposed.Finally,based on the PSCAD/EMTDC model which is consistent with actual control and protection procedures,the improved strategy is tested and analyzed.The test results show that the improved strategy can effectively avoid non-fault pole commutation failure caused by the single-pole fault on DC side.

关 键 词：直流输电 换相失败 最小换相裕度(AMIN)控制 换相裕度面积 关断角 

分 类 号：TM722[电气工程—电力系统及自动化]