特高压变电站隔离刀闸二次回路若干问题分析及改进

Analysis and Improvement on Problems in Secondary Circuit of Disconnector in UHV Substations

针对超(特)高压变电站和换流站隔离、接地刀闸设备暴露出的问题及缺陷,总结了刀闸二次回路若干问题并提出改进措施。为防止电机电流串入控制回路而烧损元器件,刀闸控制回路宜与电机回路电源独立;气体封闭绝缘组合电器(GIS)间隔整流器出口宜设置平衡电阻桥接地,以便于维护检修工作;刀闸辅助接点不宜闭锁断路器合闸,以确保断路器合闸控制回路的可靠性;针对长期带电的电子式热继电器易烧损,接有长电缆的刀闸电机接触器易发生误动事故,提出了电源接线等改进方案;指出测控装置出口继电器接点性质应与控制回路电源性质一致,并针对GIS间隔温湿度控制器与加热器分散布置的缺点给出改进意见。为刀闸设备的生产制造、系统设计和现场运维检修工作提供了参考。

For the problems of disconnector and earthing switches in EHV(UHV)substation and converter station,this paper summarizes some problems in the secondary circuit of switches and puts forward improvement measures.In order to prevent the motor current flow in series to the control circuit and burn the components,the switches control circuit and motor circuit should be seperately power supplied.The earthing balance resistance bridge should be installed at the outlet of GIS unit’s rectifier to facilitate maintenance and repair work.To ensure the reliability of circuit breaker closing control circuit,the auxiliary contact of switches should not block the closing operation of circuit breaker.For the long-term electrified electronic thermal relay is frequently burnt,and the switches motor contactor connected with long cable is easy to wrong operation,the power wiring and other improvement schemes are proposed.The nature of outlet relay contacts should be consistent with that of control circuit power supply.Disadvantage and suggestion of decentralized arrangement of GIS unit’s temperature&humidity controller and its heater is put forward.It provides a reference for the manufacture,system design and on-site operation and maintenance of switchgear.