大型水轮发电机组纯机械过速保护改造研究

Renovation of the Purely Mechanical Overspeed Protection System for Large-scale Hydro-turbine Generator Unit

通过对水轮发电机组导叶、圆筒阀纯机械过速保护系统研究分析,针对存在的系统延时及冗余问题,将纯机械过速保护装置液压阀1改造为"复归"时输出压力油,"动作"接通回油。同时,将分别控制导叶、圆筒阀的两个纯机械过速装置液压阀合并为一套。改造后对系统进行联动测试,纯机械过速保护装置从飞摆动作到导叶接力器开始动作,过速系统正常响应时间约为3 s。同时,圆筒阀系统动作可靠,及时关闭,系统改造效果良好。

The purely mechanical overspeed protection system for the guide vanes and the cylindrical valve in large-scale hydro-turbine generator unit is analyzed.To solve the delay and redundancy problems of the system,renovation measures are implemented.The hydraulic valve 1 in the overspeed protection device is renovated to deliver the pressure oil during the resetting action and connect the returning oil during the protection action.Meanwhile,the two purely mechanical overspeed protection devices that respectively control the guide vanes and the cylindrical valve are merged into one.Linkage test of the system shows that after the renovation,the normal response time of the purely mechanical overspeed protection device is about 3 seconds from the swinging action to the guide vane servomotor action.Also,the cylindrical valve system is reliable as it can close timely.Practice shows that the renovation is satisfactory.