Research on surge-control facilities for hydropower plants in Sweden

This paper reports part of the research programs aimed at the evaluation of surge-control facilities for hydropower plants. The facilities investigated include simple, throttled, closed and differential types of surge chamber. The stability of surge oscillations is analyzed by the direct method of Liapunov and the phase-plane technique. The two procedures lead to the same results for small surge perturbations about the steady state. Certain dynamical features of the hydraulic system such as Hopf bifurcation can only be achieved through nonlinear analysis. Water-hammer pressure wave transmission is also examined for some of these surge tanks. The purpose of it is to find out which type of tank transmits less water-hammer pressure under the same flow condition.