三峡右岸电站ALSTOM 20F机组接力器改造

Renovation of the Servomotor in ALSTOM 20F Unit in the Right Bank Power Plant of Three Gorges Hydropower Station

针对三峡右岸电站ALSTOM 20F机组自投产以来多次在高水头小开度区间出现导叶接力器关闭迟滞问题,分析故障产生的原因,曾采用导叶中轴套扩大内径的处理方案,机组导叶拒动现象消除5年后再次出现,经反复检查并与左岸机组对比分析,发现其核心原因为接力器操作功率偏小。研究决定将其更换为结构简单、制造容易、检修方便的接力器,并对一些部件安装方式及参数适当调整。机组改造投入运行以来再未出现异常,说明改造方案可行,施工工艺可靠。

Since the start of the operation of the ALSTOM 20F unit in the right bank power plant of Three Gorges Hydropower Station,shutdown action delaying of the guide vane servomotor is observed for many times in the high water head and small opening working condition.Treatment scheme of expanding the inner diameter of the guide vane shaft sleeve was used.But the action failure fault of the guide vanes are encountered again after the treatment.After repeated inspection and comparison with the left bank units,it is found that the essential reason of this fault is the operation power of the servomotor is too low.Thus,it is replaced with a servomotor with simpler structure and more convenient manufacturing and maintenance,and the installation mode and parameters of some components are adjusted appropriately.After the renovation,the unit operates well with no abnormality found,indicating that the renovation scheme is feasible and the construction process is reliable.