发变组过激磁保护误动作分析与处理

Analysis and Treatment of Malfunction of Over-excitation Protection of Generator Transformer

2015年8月17日某电厂1号机主变高厂变第二套保护主变过励磁保护动作,致使220kV开关站的2211和2212断路器跳开,海南核电1号机组失去主电源。本文针对该事件,通过现场提取故障记录文件,分析了事故时机组状态,并进行了保护装置校验,最终找出事故原因。后续通过多方面的讨论分析,对其中设置不合理之处进行了修改,保证了发变组的安全运行。

On August 17,2015,the over-excitation protection action of the second protector for the unit 1 main transformer in a power plant implemented,which caused the circuit breakers 2211 and 2212 at the 220kV switching station to trip and the unit 1 of the power plant lost the main power supply. In view of this incident,therecord files wereextracted,the status of the accident time group wasanalyzed,and the protection device waschecked. Finally,the cause of the accident wasfound.After the discussion and analysis in many aspects,the unreasonable settings weremodified to ensure the safety of the generator-transformer.