长尾水洞抽水蓄能电站调节稳定性及参数优化

佛子岭抽水蓄能电站采用水泵水轮机,尾水调压室的断面尺寸不满足托马稳定断面要求,尾水隧洞长达1 500 m以上,水流惯性大,在空载工况可能诱导引起频率调节的低频脉动,导致机组不能正常并网运行。文中提出了描述抽水蓄能电站调节动态特性的非线性数学模型,提出了衡量水轮机调节性能质量的附加指标———调速器参数的选择应促使调压室水位波动的快速衰减。最后通过数值仿真的方法研究调速器参数bt、Td、Tn的优化选择,不仅使水轮机孤立运行的频率调节具有较好的质量,而且使调压室水位波动快速衰减。

Governing stability and optimization of setting parameter for a pumped storage power station with long tailrace tunnel

The pump-turbine units are installed in Fuziling Pumped Storage Power Station,of which the cross-section of the surge tank on the tailrace tunnel with the length of over 1 500 m can not meet the requirement from that of Thoma's Critical Stable Sectional Area.Thus,a low frequent fluctuation may be induced by a large inertia of the flow during the idle motion,and then the units can not be normally put into the parallel operation concerned with the power network.A non-linear mathematical model is presented herein to describe the dynamic performance of the governing system for station,and furthermore,the additional index to evaluate the governing performance of the pumpturbine is put forward,that is that the selection of the governor parameters must promote the quick attenuation of the fluctuation of the water level in the surge tank.At last,the optimal selection of the governor parameters-b_t,T_d and T_n is made with numerical simulation.In this way,not only the frequency of the turbine during the isolated operation has a better quality,but the water level in the surge tank can also be attenuated quickly.