水斗式水轮机特性对系统运行稳定性的影响

Influence of pelton turbine's characteristics on operation stability

冲击式水电站的运行稳定性成为目前日益关注的问题。从理论上研究了水斗式水轮机特性对水电站运行稳定性的影响。首先在理想PI调速器、刚性水击、单管单机条件下,加入自由出流方程,求解出计入水斗式水轮机特性的小波动稳定判别式。然后结合水斗式水轮机的运行特点,建立目标函数,经分析,得出了水斗式水轮机在等出力变幅时的小波动最不稳定区,并用数值计算对其加以验证。最后提出,对于多喷嘴水斗式水轮机来说,应根据不同的喷嘴个数情况,分别作稳定校核计算。

The operation stability of the hydropower station euipped with pelton turbine is increasingly concerned. We theoretically studied the influence of pehon turbine＇ s characteristics on operation stability of the station. Under the conditions of ideal PI governors, rigid water hammer, single - pipe and single - unit, and using free outflow equation, the discriminant of small fluctua- tion stability with consideration of pelton turbine＇ s characteristics is deduced. Considering the pelton turbine＇ s operation fea- tures, the objective function is established and the most unstable area of small fluctuation under the equal output amplitude is suggested and verified by numerical calculation. It is proposed that for the pelton turbine with multiple nozzles, stable check calculation should be eondueted according to the nozzle number.