某变速抽蓄机组水泵水轮机发电工况压力脉动试验研究  

Experimental Study on Pressure Fluctuation of a Pump-Turbine in a Variable-speed Pumped-storage Unit under Power Generation Condition

作　　者：李瑶 马智杰[1,2,3] 孙博志 LI Yao;MA Zhijie;SUN Bozhi(China Institute of Water Resources and Hydropower Research,Beijing 100038,China;School of Electrical and Information Engineering,Tianjin University,Tianjin 300072,China;North China Power Engineering Co.,Ltd.,Beijing 100120,China)

机构地区：[1]中国水利水电科学研究院,北京100038 [2]天津大学电气自动化与信息工程学院,天津300072 [3]华北电力设计院有限公司,北京100120

出　　处：《水力发电》2023年第11期94-102,共9页Water Power

基　　金：国家重点研发计划项目(2018YFB0905200)。

摘　　要：在水泵水轮机中,工程界的观测表明,压力脉动已成为最严重的水力失稳现象之一。压力脉动会引起机组的振动和疲劳失效,甚至引起厂房的振动,极大地影响电站的安全稳定运行。在变速抽蓄技术得到越来越广泛应用的趋势下,变速机组运行过程中的压力脉动成为影响变速机组稳定性及其发展的重要因素,为探究变速机组的运行稳定性,基于全功率变速抽水蓄能机组水泵水轮机发电工况下的压力脉动进行了研究。对水泵水轮机真机在水轮机工况寻优变转速运行后的各部位压力脉动进行分析,并得到以下结论:无叶区压力脉动最为剧烈,其受到的动静干涉影响最大,而离转轮区域越远,受到动静干涉的影响越小;尾水管由于尾水管涡带的原因,存在一定的低频脉动;变速机组经过变速寻优后的工况,压力脉动情况良好,压力脉动系数C p均处于10%以内,变速机组的寻优运行路径使得水泵水轮机总是处于较好的工况点,对于内流流态等的改善有很大帮助。The engineering observations have shown that the pressure pulsation has become one of the most serious hydraulic instability phenomena in pump-turbines.The pressure pulsation can cause the vibration and fatigue failure of unit,and even the vibration of powerhouse building,which greatly affects the safe and stable operation of power station.In the trend of increasingly application of variable-speed pumped-storage technology,the pressure pulsation during the operation of variable-speed units has become an important factor affecting the stability and development of variable-speed units.To explore the operational stability of variable-speed units,the pressure pulsation under power generation condition of pump-turbine of a full-power variable-speed pumped-storage unit is studied.The pressure pulsation of each part of pump-turbine after the real turbine running at variable speed after the optimization of turbine operating condition is analyzed,and following conclusions are obtained:(a)the pressure pulsation in the vaneless area is the most intense and it is most affected by the dynamic and static interference,while the farther away from the runner area,the less affected by the dynamic and static interference;(b)the draft tube has a certain low-frequency pulsation due to the vortex rope in the draft tube;and(c)after variable speed optimization,the pressure pulsation of the variable-speed unit is good,and the pressure pulsation coefficient C p is all less than 10%,indicating that the optimization operation path of variable-speed unit makes the pump-turbine always in a good operating point,which is greatly helpful for improving the internal flow pattern.

关 键 词：变速抽水蓄能技术 水泵水轮机 压力脉动 现场试验 尾水管涡带 变速机组 变速寻优 

分 类 号：TV743[水利工程—水利水电工程]