考虑水轮机特性项的尾水调压室临界稳定断面公式研究

Research on the Critical Stable Cross-sectional Area of the Tailrace Surge Chamber Considering the Hydraulic Turbine Characteristics

为了进一步研究水轮机特性对于调压室临界稳定断面的影响,结合调压室及水道局部模型、发电机及负荷局部模型、调速器局部模型,利用传递函数的思想,推导出了包含水轮机特性项的尾水调压室稳定断面直接表达公式,其中水轮机特性项可直接采用经验公式进行估算;实际工程案例分析表明,与规范公式相比,该公式计算结果与数值分析结果更为一致,安全性更高,因此采用推导的考虑水轮机特性的尾水调压室稳定断面公式有利于保障实际工程的安全。

In order to further study the effect of hydraulic turbine characteristics on the critical cross-sectional area of a surge chamber, the surge chamber and channel model, generator and load model as well as the governor model are established in this paper firstly. Then these models are combined and solved by using the transfer function theory and the formula for the direct calculation of critical cross-sectional area of a tailrace surge chamber is deduced. In this deduced formula the turbine characteristics coefficient can be estimated by the empirical formula directly. Practical engineering cases show that the critical cross-sectional areas calculated by the formula deduced in this paper are closer to reality compared to those by the standard formula, which means that the hydranlic turbine characteristics are essential to the stability of the system. To ensure engineering safety, the turbine characteristics should be considered.