基于极间耦合特性的特高压直流换相失败预防方法  

Prevention Method for Commutation Failure of UHVDC Based on Interelectrode Coupling Characteristics

作　　者：李新年 付颖 张庆武[3] 林少伯 雷霄 许锐文 LI Xinnian;FU Ying;ZHANG Qingwu;LIN Shaobo;LEI Xiao;XU Ruiwen(State Key Laboratory of Power Grid Safety and Energy Conservation(China Electric Power Research Institute),Beijing 100192,China;State Grid Corporation of China,Beijing 100031,China;NR Electric Co.,Ltd.,Nanjing 211102,China)

机构地区：[1]电网安全与节能国家重点实验室(中国电力科学研究院有限公司),北京市100192 [2]国家电网有限公司,北京市100031 [3]南京南瑞继保电气有限公司,江苏省南京市211102

出　　处：《电力系统自动化》2022年第23期170-177,共8页Automation of Electric Power Systems

基　　金：国家电网公司科技项目(5100/202022011A)。

摘　　要：换相失败是晶闸管换流阀逆变器的常见故障。随着高压直流输电的不断发展,直流输电的电压等级和输送容量不断提升,交直流系统间的相互影响加剧,直流换相失败对交流系统的影响日益凸显。随着直流输电距离的增长,双极直流线路的相互影响更为明显,直流系统一极发生线路故障可能会导致另外一极发生换相失败。文中通过研究双极直流线路间的耦合机理,提出直流电压突变量指标判定与优化逆变侧关断角控制相结合的换相失败预防控制方法。该方法基于直流线路间的电磁耦合特性,根据健全极直流电压、电流特征,优化关断角调节器,利用直流电压突变量原理判别故障极,通过增大关断角,避免健全极发生换相失败。电磁暂态仿真和实际工程应用验证了所提方法的有效性。Commutation failure is a common fault of inverters with thyristor converter valve. With the continuous development of high voltage direct current(HVDC) transmission, the voltage level and transmission capacity of DC transmission keep increasing,and the interaction between AC and DC systems is intensifying. The impact of DC commutation failure on AC systems is increasingly prominent. With the increase of DC transmission distance, the interaction between bipolar DC lines is more obvious.The line fault at one pole of DC system may lead to the commutation failure at the other pole. By studying the coupling mechanism between bipolar DC lines, this paper proposes a prevention control method for commutation failure which combines the determination of DC voltage sudden-change index with the optimization of inverter-side turn-off angle control. This method is based on the electromagnetic coupling characteristics between DC lines, optimizes the turn-off angle regulator according to the characteristics of DC voltage and current of the sound pole, uses the principle of DC voltage sudden-change to identify the fault pole, and avoids the commutation failure of the sound pole by increasing the turn-off angle. The effectiveness of the proposed method is verified by the electromagnetic transient simulation and the practical engineering application.

关 键 词：特高压直流输电 换相失败 极间耦合 预防控制 电磁暂态 

分 类 号：TM721.1[电气工程—电力系统及自动化]