水轮发电机电气事故停机流程可靠启动研究

Study on Reliable Start up of Hydraulic Generator Electrical Emergency Shutdown Process

针对三板溪水电站发电机组在并网运行过程中差动保护动作未启动电气事故停机流程的事件,从保护装置动作、电气事故停机流程、计算机监控系统下位机PLC等方面进行了深入研究,发现根本原因为发电机保护动作时间小于计算机监控系统下位机PLC的扫描周期,并提出三种解决方案。修改保护装置配置延长保护动作信号,或将保护动作信号接入扫描周期较短的水机保护PLC中,扩展保护动作信号,反送至主PLC中,或选择性能更优的PLCo试验结果表明三种方案均能正确启停电气事故停机流程、保障机组安全稳定运行。

In view of the event that the differential protection action did not start the electrical accident shutdown process during the grid connected operation of the generator units of Sanbanxi Hydropower Station,an in—depth study was carried out from the aspects of the protection device action,electrical accident shutdown process,the lower computer PLG of the computer monitoring system,etc.It was found that the fundamental reason was that the generator protection action time was less than the scanning cycle of the lower computer PLC of the computer monitoring system,and three solutions were proposed:modifying the protection device configuration to extend the protection action signal;connecting the protection action signal to the water turbine protection PLC with short scanning period,in order to expand the protection action signal and.send it back to the main PLC;or selecting a PLC with better performance.The test results show that all of the three schemes can correctly start and stop the electrical emergency shutdown process and ensure the safe and stable operation of the unit.