上汽西门子超超临界660MW机组甩负荷试验异常分析及处理

Anomaly Analysis and Treatment for Load Shedding Test of SAIC Siemens Ultra-Supercritical 660 MW Unit

上汽超超临界西门子机型机组实际甩50%额定负荷转速飞升至3 196 r/min,为查找转速飞升值过大的原因,通过对甩负荷试验数据及该类型机组超速保护控制逻辑的分析,设计了3种处理措施,并且对3种处理措施下的理论转速飞升值进行了静态预测,从而确定了第一次甩负荷试验转速飞升高的原因。依据静态预测结果,将调门快关动作信号扫描方式由"Slow"修改为"Fast",同时在DEH控制器C20指令与ETS控制器调门快关信号之间增设硬接线,再次进行了甩50%额定负荷试验,转速最高飞升至3 104 r/min,满足甩负荷试验导则要求。

The actual 50% rated load shedding of SAIC Siemens ultra-supercritical unit led to 3 196 r/min speed soaring. In order to find out the reason of speed over-soaring, the load shedding test data and the overspeed protection control logic were analyzed. Three kinds of treatment measures were designed, and static prediction was conducted for the theoretical soaring values of the three measures, so as to determine the reason of speed soaring in the first load shedding test. According to the static prediction results, the scanning mode of the quick closing motion signal was modified from "Slow" to "Fast". Meanwhile, hard wiring was added between the C20 command of DEH controller and the quick closing signal of ETS controller. The 50% rated load shedding test was conducted again, and the maximum speed soared to 3 104 r/min, meeting the requirements of the load shedding test guidelines.