某电厂汽机DEH控制系统故障原因的探讨

Cause Analysis on Steam Turbine DEH System faults of a Power Plant

某电厂150MW机组调试启动过程中,汽机DEH系统多次出现故障,表现为:抗燃油系统压力频繁波动,高、中压调门上下摆动,高压主汽门和低压调门有时也摆动,机组负荷出现大幅度晃动现象,严重时导致机组跳闸或甩负荷;低压调门还常发生卡涩,单阀切顺序阀运行时负荷出现波动。结合现场处理情况,对故障原因展开理论分析。

During the commissioning and start-up of one 150MW steam turbo-unit, as to the DEH system, some faults occurred, such as, fire-resistant oil system pressure frequently fluctuated, HP and IP regulating valves swayed, sometimes HP stop valves and LP regulating valve also swayed, consequently, turbo-unit load increased or decreased largely, even it resulted in tripping or load rejection, Additionally, jam faults sometimes happened to LP regulating valve. Load fluctuation occurred when switching from single valve to sequential valve operation, Based on the control theory, the paper analyzed the malfunction causes concerning the realities.