强感应电环境下500kV变电站接地线防弧装置

Device of Earth Wire Arc Preventing in 500 kV Substation under Strong Induced Electricity Environment

检修过程中电气设备感应电压过高,当接地刀闸无法操作时需挂接临时接地线,挂接时引发的电弧故障影响设备安全运行。基于此,提出一种基于限流电抗器的接地线切换系统,该系统可以补偿瞬时电流,降低电压水平。工作过程中将过电压限制到合理值后,通过控制系统将接地状态切换为直接接地。应用结果表明,该装置不仅可有效防止接地过程感应电压产生的接地电弧,而且应用便捷、安全性高,能够大幅提高检修效率。

The induced voltage of the electrical equipment is too high during the overhaul.When the grounding switch can not be operated,it is necessary to connect the temporary grounding wire.The arc fault will affect the safe operation of the equipment.In this paper an anti-arc device for temporary grounding wire hanging is developed,and a grounding wire switching system based on the current limiting reactor is presented.This system can compensate the instantaneous current,and reduce the overvoltage level.Moreover,when the overvoltage is limited to a reasonable value,the grounding state is switched to direct grounding by control system.The application results show that the device can prevent the grounding arc caused by the induced voltage in the grounding process effectively,has the advantages of convenient installation and high security,and improve the efficiency greatly.