顺北油田二区变电站35kV电压互感器烧毁故障分析OA

During the operation of power grid in the oilfield,the 35kV and 10kV systems are neutral grounded or ungrounded systems through arc suppression coils.During the development period of the power grid,the system parameters may be in the resonance zone,and electromagnetic voltage transformers are prone to ferromagnetic resonance,generating overvoltage or overcurrent.In severe cases,the voltage transformers may be burned out.In this paper,three voltage transformer burn-out faults occurred in Shunbei No.2 substation are studied.The conclusion is drawn that the power system is in the resonant region,and the ferromagnetic resonance of voltage transformer is the cause of voltage transformer burn-out.By adopting measures such as investing arc suppression coils,applying voltage transformers with good saturation characteristics,and renovating 4PT,ferromagnetic resonance is effectively controlled.