平凉电厂#3机励磁系统切换异常分析研究

Abnormal analysis of Pingliang power plant #3 excitation system switch

华能平凉电厂#3发电机励磁系统由A、B两套组成且调节器可以运行在恒电压、恒电流、恒功率因数3个通道,还配有备励通道。在机组投运初期进行过电压与电流通道切换,且两个通道切换时各个监控量数据正常平稳。2014年#3机组大修后在做励磁调节器双套电压通道切换备励时,发生发电机转子电压、转子电流、定子电流、无功功率剧烈摆动。经过调取事故发生时的录波图形,通过详细的理论分析,对励磁调节器的参数进行修正,成功解决了电压通道与备励通道不能切换问题。经实践证明,系统改造后电压通道与备励通道可以可靠切换,目前应用于#2、#3、#4机组。

Huaneng Pingliang power plant #3 generator excitation system consists of A, B and sets consisting regulator can run at three channels induding a constant voltage, constant current and constant power factor, as well as spare excitation channel. In the early days operation of over-voltage and current channel switching were carried out, and during switching the two channels monitoring data were normal and stable. After 2014 #3 overhaul, double sets of excitation voltage regulator channel switched to spare excitation channel, resulting in dramatic swing voltage generator rotor, rotor current, stator current, reactive power. After calling the recorded wave graphic when the accident occurred, through detailed theoretical analysis, the parameters of the excitation correction were adjusted, and the problem of switching was solved successfully. Practical exPerience proved that after reformed the transformation voltage channel and the spare excitation channel of the system can reliably switch, which currently are used in #2, #3, #4 units.