Abstract
Closed air cushion surge chambers have economically contributed to construction of hydroelectric power plants in Norway. To apply this type of chambers to our geological and topographical conditions in Japan, however, requires 1) the review of the equation for calculating the volume of the chambers, derived by R. Svee to secure the stability of oscillation in a hydraulic system, and 2) the feasibility study for minimizing the volume. In this paper, the portion R. Svee expressed by means of the governor equation that Thoma had used is expressed by applying a speed governor, the inertia of rotation part of a turbine-generator unit, the hydraulic characteristics of the turbine, and parallel running of power plants. Then the equation representing the stability of surge oscillations has been derived and generalized charts are nondimensionally illustrated to show the minimum volume of the chambers. Furthermore, in the course of this study, the stability equation for a hydraulic system not equipped with a surge tank has also been derived.
