Control system for variable speed water-wheel generator apparatus

Abstract

A control system for a variable speed water turbine generator apparatus includes a first function generator that is responsive to an output command signal. The first function generator produces a rotation number command signal. A speed adjuster produces an output signal in accordance with a different signal between the first function generator output and an actual rotation number. An adder adds the generator output command signal to the speed adjuster output signal to determine an overall output command signal. An output aduster produces an output signal in accordance with a difference between the adder output and an actual power output of the generator for controlling the firing angles of the frequency converter. A second function generator, responsive to the generator output command signal, determines an opening command signal for the variable opening vanes. An opening adjuster produces an output signal in accordance with a difference signal between the second function generator output and an actual opening of the variable opening vanes to control the variable opening vanes. The first and second function generators increase command values for the rotation number and the variable opening vanes, respectively, as the output command signal increases. The frequency converter is further controlled to maintain the rotation number within a predetermined operation range.