The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 15, 1987
Filed:
Sep. 24, 1986
Eiji Haraguchi, Ibaraki, JP;
Hiroto Nakagawa, Osaka, JP;
Akira Bando, Hitachi, JP;
Takao Kuwahara, Hitachi, JP;
Haruo Nohara, Hitachi, JP;
Kenichi Ono, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
The Kansai Electric Power Co., Inc., Osaka, JP;
Abstract
A control system for variable speed hydraulic turbine generator apparatus comprises an induction generator connected at its primary side to an AC power line system, a secondary excitation controller connected to the secondary side of the induction generator and being responsive to a generator output command signal supplied externally to supply to the induction generator an excitation current which causes the induction generator to generate AC power at the same frequency as that on the AC power line system, a hydraulic turbine for rotating the induction generator, a guide valve for regulating the amount of water supplied to the hydraulic turbine, a rotation speed detector for detecting a rotation speed of the induction generator, a rotation speed command calculator for receiving a hydraulic turbine running condition signal inclusive of the external generator output command signal and calculating an optimum rotation speed command, a rotation speed controller for comparing the optimum rotation speed command with a rotation speed signal from the rotation speed detector and producing a guide valve opening control signal in accordance with a difference between the optimum rotation speed command and the rotation speed signal, and a guide valve driver responsive to the guide valve opening control signal to deliver to the guide valve a signal which controls the opening of the guide valve in accordance with the guide valve opening control signal.