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. 26, 1989
Filed:
Jan. 15, 1988
Yosio Furukawa, Hitachi, JP;
Yasuhiro Yasaka, Hitachi, JP;
Osamu Nagura, Katsuta, JP;
Eiji Haraguchi, Ibaraki, JP;
Hiroto Nakagawa, Osaka, JP;
Yasuteru Oono, Kobe, JP;
Hitachi Ltd., Tokyo, JP;
The Kansai Electric Power Co., Inc., Osaka, JP;
Abstract
A variable-speed power generating system comprises a variable-speed generator electrically connected at its primary winding to an electric power system and its secondary winding to the electric power system through a frequency converter and mechanically coupled to a driver driving the secondary side thereof, a phase detector generating an output signal representing a slip frequency in response to the application of a first input having a frequency component of an output generated from the primary winding of the variable-speed generator and a second input having a frequency component corresponding to the rotation speed of the driver, a controller controlling the frequency converter on the basis of a reference phase provided by the output signal of the phase detector, and regulating means for controlling the frequency converter so that, when the variable-speed generator is disconnected from the electric power system, the frequency applied to the secondary winding of the variable-speed generator may not deviate from a predetermined allowable range of variable frequency operation of the frequency converter.