基于电站最优维护信息系统的机组机械振动分析

葛洲坝水电站是我国在长江干流上自主设计的第一座大型水电站，共安装有2台单机容量为175 MW、19台单机容量为125 MW（改造前）、1台装机容量为20 MW的轴流转桨式水轮发电机组。从首台机组发电至今，葛洲坝电厂累计运行超过35 a。长时间的运行使机组出现老龄化的同时也存在着稳定性、安全性方面的隐患。基于电站最优维护信息系统(HOMIS)，对葛洲坝电厂10号机组进行了状态检测，结果发现机组存在上导X/Y向摆度、水导X/Y向摆度过大的问题，为此，借助于HOMIS集成的快速傅里叶变换函数进行诊断，结果诊断出上导、水导摆度的主频为1 Hz,表明该现象为主轴或其附件引起的机械故障。依据机组诊断结论，经分析研究，提出了适宜的检修方案，并根据方案最终对磨损连杆进行了更换处理。最后，对检修前后的机组状态进行了对比，对比结果表明，检修质量达到了预期目标。

Study on mechanical vibration of No.10 hydroelectric unit in Gezhouba Power Plant based on Hydropower Optimal Maintenance Information System

Gezhouba Power Plant,located on Yangtze River stem,is the first self-designed large hydropower station in China,installed with 2 power units with the capacity of 175 megawatts,19 power units with the capacity of 125 megawatts and 1 power unit with the capacity of 20 megawatts.Gezhouba Power Plant has run for more than 35 years since the operation of its first unit.The long-term operation ages the units and causes hidden dangers in the stability and safety.We checked the state of No.10 hydroelectric unit based on Hydropower Optimal Maintenance Information System(HOMIS),which showed that the swings of upper guide bearing and turbine guide bearing were excessive.It was derived that the basic swing frequencies of upper guide bearing and turbine guide bearing are 1HZ,showing that it was caused by the mechanical failure of the principal axis or its attachment.According to the diagnosis,the proper overhaul scheme was given and the worn connecting rod was replaced.The quality evaluation was made by comparing the unit state before and after the maintenance.