抽水蓄能电站上游调压室最高涌浪控制工况研究

抽水蓄能电站的水力单元通常布置两台或两台以上机组,相继甩负荷发生的概率高,有可能是上游调压室最高涌浪的控制工况。本文从调压室基本方程出发,推导任意时刻甩负荷调压室最高涌浪隐式公式。将相继甩负荷工况和先增负荷后甩负荷工况的最不利叠加时刻作为初始条件带入隐式公式中,分析得出抽水蓄能电站上游调压室最高涌浪的控制工况:即在阻抗损失系数逐渐增大的情况下,控制工况由先增后甩叠加工况变成相继甩负荷工况。该结论由实际电站的数值模拟得到了验证。

Study on control conditions of highest surge in upper surge chamber of pumped storage power stations

There is a high probability to operate successive load rejections when more than two units share one main pipe, which is generally adopted at pumped storage power stations. This condition could be a control condition of the highest surge in upper surge chamber. This paper derives an implicit formula for calculating the highest surge following load rejection at any time using the basic equation of wave motion of surge chamber, and calculates the surge-tunnel discharge relationship for the condition occurring at the worst surge wave superimposition owing to successive load rejections or other unfavorable superimposition conditions. By the results of the implicit formula taking this relationship as initial condition, we come to the conclusion that the control condition is shifting from load-increment-then-rejection condition toward successive load rejections as the hydraulic resistance coefficient of throttled surge chamber increases. Numerical simulations of an example pump-storage project are included for verification of the conclusion.