摘要
在仙游抽蓄电站机组调相转抽水的过程中,由于导叶开启过快,使得电机功率改变量较大,导致电网频率波动较大。对此,本文提出了在泵工况采用导叶分阶段线性启动的解决方法。基于高扬程水泵水轮机模型转轮特性数据,研究了不同导叶开度时机组运行的稳定性;分析了水泵流量、轴功率、效率与扬程和导叶开度的关系,提出了确定泵工况高效经济运行最大导叶开度的方法。通过对水泵和水轮机工况区压力脉动的比较分析,得出水轮机工况的压力脉动比水泵工况相同位置的大得多,所以水泵工况也可以采用导叶开度分阶段开启方式的重要结论。对水泵零流量工况的分析表明,当水泵启动时,采用缓慢开启导叶的方式有利于避免发生较大的零流量压力脉动现象。同时,选择较小的导叶开启目标开度有利于减小零流量压力脉动强度。最后,水力过渡过程计算示例表明,在水泵启动过程每个阶段导叶保持不变的过程中,水压和轴功率波动幅度较小且很快衰减,机组能够稳定运行,发生超过水轮机工况压力脉动的风险微小。由于高水头或高扬程水泵水轮机转轮单位流量和力矩特性及压力脉动具有类似特点,上述结论也可供其它抽蓄电站参考。
During the pumping operation of pump-turbine units in the Fujiang pumped storage power plant,the motor power varies greatly because of a short vane opening period,causing severe fluctuations in the grid frequency.To stabilize the operation,this paper formulates a scheme of staged linear vane opening for this plant.We examine the stability of unit operation under different vane openings based on the experimental data of a high-lift model runner,and develop a method to find the maximum vane opening for efficient and economical pumping operation through analysis on the relationships of vane opening and working head versus pump flow,shaft power and efficiency..Comparative analysis on the pressure pulsations in pumping and generating modes reveal that the pressure pulsations in generating mode are much stronger than those in pumping modes,and that the scheme of staged linear vane opening also improves pumping operation.An analysis of the pumping operation in zero flow condition shows that during pump startup,either slow vane opening operation or a smaller target vane opening helps eliminate large pressure pulsations at zero flow.Calculations of the hydraulic transients show that at each stage of the pump startup in the staged linear opening scheme,fluctuations in water pressure and shaft power are weak and decay more quickly,the units run more stably,and the risk of pressure pulsations stronger than those in generating modes is very low.The conclusions above are also useful for other highlift pump storage stations with similar unit flow,torque and pressure pulsations of the runners.
作者
肖洋
杨开林
宋少群
王官宏
马世俊
XIAO Yang;YANG Kailin;SONG Shaoqun;WANG Guanhong;MA Shijun(Power System Institute,China Electric Power Research Institute,Beijing 100192;Hydraulics Institute,China Institude of Water Resources and Hydropower Research,Beijing 100038;Dispatch&Control Center,State Grid Fujian Electric Power Corporation,Fuzhou 350003)
出处
《水力发电学报》
EI
CSCD
北大核心
2019年第4期169-178,共10页
Journal of Hydroelectric Engineering
基金
国网福建省电力有限公司重大科研项目(1706-00491)
关键词
抽水蓄能机组
泵工况
导叶分段线性开启
效率
压力脉动
pumped storage unit
pumping mode
staged linear vane opening
efficiency
pressure pulsation
