水轮发电机转子动态接地故障的检查与处理

Checking and Disposing the Dynamic One-point-grounding Fault of a Hydroelectric Generating Set

鱼跳水电站发电机在低速起动时一切正常,但是当转子转速达到或超过300 r/min时,保护发出发电机转子一点接地信号,这属于明显的动态接地情况。动态接地的原因有许多,鱼跳水电站发生的一次动态接地故障的现象,查找出其原因是由于转子磁极的铝支撑的环氧垫板缺损所致。经过改进和修复效果很好。

When the generating set starts up at a low speed, everything works well. As soon as the rotor turns at or over a speed of 300 r/min, the protection system warns that a one-point-grounding fault is arising from the rotor winding. It clearly shows that there is a dynamic grounding fault in rotor windings. Many reasons maybe lead to such kind of fault. This paper will introduce how we checked, test, analyzed and disposed the dynamic grounding fault during an accident occurred at Yutiao Hydropower Station.