Variable-speed pumped-storage power generating system.

摘要

A variable-speed pumped-storage power generating system includes a variable-speed driver composed of a generator/motor (l) and a frequency converter (4) connected to an electric power system (5) and a pump/turbine (6) driven by the generator/motor. The power generating system comprises an optimum rotation speed function generator (l2) calculating, on the basis of at least an externally applied output command signal, an optimum rotation speed of the motor for driving the pump with high efficiency, a speed detector (2) generating a speed detection signal by detecting the actual rotation speed of the motor, a speed regulator (l6) receiving the output signals of the function generator and speed detector to generate an output correction signal for decreasing the speed error to zero, an adder (l0l) adding the output correction signal to the output command signal, a comparator (l02) comparing the output signal of the adder with an output power detection signal generated from a motor output detector (40) and generating an error signal therebetween, and an output regulator (8) controlling the excitation of the secondary winding of the motor through the frequency converter to decrease the output power error to zero, thereby controlling the output and rotation speed of the motor. The power generating system also comprises an optimum guide-vane opening function generator (l3) calculating an optimum guide vane opening on the basis of at least the output command signal, a comparator (l03) comparing the output signal of the second function generator with a guide-vane opening detection signal from a guide-vane opening detector (70), and a guide-vane opening regulator (9) controlling the opening of the guide vanes according to the result of comparison.