大功率晶闸管反向恢复期保护逻辑的优化设计  

A Logic Optimization Design for High Power Thyristor Reverse Recovery Period Protection

作　　者：陶敏[1] 梁家豪[1] 梁秉岗[1] 刘道民 刘宏 柴斌 TAO Min;LIANG Jiahao;LIANG Binggang;LIU Daomin;LIU Hong;CHAI Bin(Guangzhou Bureau,China South Power Grid EHV Power Transmission Company,Guangzhou 510000,Guangdong,China;C-EPRI Electric Power Engineering Co.,Ltd.,Beijing 102200,China)

机构地区：[1]中国南方电网有限公司超高压输电公司广州局,广东广州510000 [2]中电普瑞电力工程有限公司,北京102200

出　　处：《电气传动》2022年第2期36-39,共4页Electric Drive

摘　　要：晶闸管是特高压直流输电领域中的核心设备,其运行状态直接影响了直流输电系统的稳定性。晶闸管关断过程中,电流从额定值降为零后,才具备承受反向电压的能力。由于晶闸管结电容的存在,需要一定的反向恢复电荷,使得电流过零后反向流动,这一过程称为反向恢复期。如果晶闸管在反向恢复期内端电压突然升高,斜率超过一定值后,晶闸管就会被击穿,所以需要在反向恢复期内监视晶闸管端电压,一旦电压上升率超过一定值,就必须立刻触发晶闸管,保护晶闸管不被击穿。提出了一种应用于大功率晶闸管反向恢复期保护逻辑信号的优化方案,并通过硬件电路实现。通过仿真分析及硬件电路试验测试,验证了该方案无延时的保护效果,证明了该方案在晶闸管反向恢复期保护中的优越性。The thyristor is considered as the core equipment in the field of high voltage direct current(HVDC)transmission. The stability of the direct current(DC)transmission system is directly affected by the operation state of the thyristor. During the turn-off period,the thyristor can withstand the reverse voltage only after the current drops from rated value to zero. A certain reverse recovery charge is required to make the zero-crossing current flow reversely due to the existence of the thyristor junction capacitance,this process is called the reverse recovery period.During the reverse recovery period,the thyristor will be broken if the voltage gradient exceeds a certain value.Therefore,it is necessary to monitor the voltage of the thyristor terminal during the reverse recovery period. Once the voltage gradient exceeds a certain value,the thyristor must be triggered immediately to protect the thyristor from breakdown. An optimization scheme for the high-power thyristor protection logic signals in the reverse recovery period was presented and realized by hardware circuits. The effect and the superiority of the undelayed protection in the reverse recovery period of the scheme were verified through simulation analysis and hardware circuit tests.

关 键 词：大功率晶闸管 反向恢复 换流阀 晶闸管电子板 

分 类 号：TM726.1[电气工程—电力系统及自动化]