继电器线圈接地故障现象分析

保护控制设备中,存在大量的逻辑控制、出口跳合闸等继电器回路,此类继电器的误动作,可直接导致保护、控制设备的误动或拒动。当继电器线圈回路发生直流接地故障时,该继电器是否发生误动作,与接地检测的桥电阻、直流系统正负极对地绝缘电阻、正负极对地分布电容,继电器线圈内阻、实际动作电压、动作时间等有关。从理论计算、试验和现场检验等方面对这些问题进行了研究探讨,研究结果验证了分析的正确性。

Research on grounding fault of relay coils

There are many relay circuits such as logical control,closing exports and export trip,etc.in protective and control apparatus.The misoperation of this kind of relay may result in malfunction or vibration of the related protective and control apparatuses directly.It is proved that the maloperation are related with the bridge resistance,the pole insulation resistance of DC system,the spray capacitance between poles,the resistance of relay coils,actual operative voltage and action time,etc.Such problems are discussed in this paper from theoretical calculation,laboratory experiments and field tests.The correctness of the analysis is verified by the results.