摘要
在励磁系统中,发电机出口电压互感器(PT)是测量发电机机端电压的重要装置,因保险管老化、质量不良等原因,高压保险熔断时其二次侧电压会出现缓慢下降的现象,从而使运行机组有较高的误强励误跳机风险。通过分析探索,在原有的“PT断线”保护逻辑上新增PT慢熔判据,作为励磁系统检测机端PT断线的补充,从而有效降低了机组发生PT慢熔导致事故停机的风险。
In excitation system of generator unit,the generator outlet potential transformer(PT)is an important device for the measurement of the outlet voltage.Due to the ageing or poor quality of the fuse tube,the secondary side voltage of the high-voltage fuse may slowly drop down when the fuse melts,which will increase the risk of faulty forced excitation and tripping of the operating unit.Analysis shows that a slowly melting identification criterion added in the original PT disconnection protection logic can be a useful supplement and effectively reduce the risk of accidental shutdown due to PT slow melting.
作者
郭超
祝家平
胡婉倩
GUO Chao;ZHU Jiaping;HU Wanqian(Baihetan Hydropower Plant, China Yangtze Power Co., Ltd., Ningnan 615400, China)
出处
《水电与新能源》
2021年第6期75-78,共4页
Hydropower and New Energy
关键词
PT
断线
慢熔
误强励
慢熔判据
PT
disconnection
slow melting
faulty forced excitation
slow melting identification criterion
