蒲石河抽水蓄能电站1号机转轮改造水力稳定性研究与实践

Research and Practice of Hydraulic Stability Reconstruction of No.1 Unit Runner of Pushihe Pumped-storage Power Station

蒲石河抽水蓄能电站自运行以来,机组和厂房振动强烈,给电站带来较大的安全隐患,迫切需要采取措施降低振动。为解决该振动问题,经现场测试数据分析,认为引起水电站厂房100Hz异常振动和噪声的主要激振力是由动静干涉诱发引起的。因此采用了9叶片转轮更换为7叶片转轮的错频降振改造措施。本文通过数值计算、模型试验和真机现场测试等方法,重点比较了7叶片转轮与原9叶片转轮的无叶区压力脉动幅值和现场振动情况。模型试验结果表明,经水力优化,7叶片转轮无叶区压力脉动幅值整体低于原9叶片转轮;同时,改造后原型机现场运行情况表明,机组和厂房异常振动消失,机组振摆、噪音及振动水平均大幅降低,证明了该方案的有效性和可行性,研究成果可应用到具有相同振动问题的抽水蓄能电站的改造中。

Since the operation of pushihe pumped-storage power station,the unit and workshop have been vibrated strongly,which has brought great potential safety hazards to the power station.It is urgent to take measures to reduce the vibration.In order to solve the vibration problem,the analysis of the field test data shows that the main excitation force that causes the abnormal vibration and noise of the hydropower plant at 100 Hz is caused by the static and dynamic interference.Therefore,the staggered frequency vibration reduction measures of replacing the 9-blade runner with the 7-blade runner are adopted.This paper focuses on comparing the pressure pulsation amplitude and field vibration of the 7-blade runner and the original 9-blade runner through numerical calculation,model test and real machine field test.The model test results show that,after hydraulic optimization,the pressure pulsation amplitude in the non-blade area of the 7-blade runner is generally lower than that of the original 9-blade runner,and the dynamic and static interference frequency division amplitude is greatly reduced.The abnormal vibration of the unit and the powerhouse disappeared,and the vibration,noise and vibration levels of the unit were greatly reduced,which proved the effectiveness and feasibility of the scheme.The research results can be applied to the reconstruction of the pumped storage power station with the same vibration problem.