公伯峡水电站发变组后备保护存在问题及功能完善

Existent Problems in Gongboxia Hydropower Station Generator-transformer Unit with Back-up Protection and Perfection

针对公伯峡水电站发变组后备保护中,在机组故障时由于发电机灭磁时间长,对后备保护电流记忆功能产生影响,造成机组解列后误跳母线联络断路器的问题进行了分析探讨,采取了在发电机相间后备保护及主变高压侧接地后备保护动作于跳母联开关时,加判主变高压侧开关并网状态的措施,对电网的安全运行起到了良好的作用。

This paper takes analysis and discussion on problem of bus-tie circuit breaker fault trip after unit disconnecting in backup protection of Gongboxia hydropower station＇s generator-transformer unit that occurs because of generator in long time demagnetization during unit malfunction, therefore it imposes influence on memory function of backup current protection, after adopting measure of distinguishing grid-connected condition of main transformer＇s high voltage side switch when generator interphase backup protection and main transformer＇s high voltage side grounding backup protection acting on tripping bus-tie circuit breaker, it produces favorable effect on safe operation of power grid.