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:
Feb. 03, 2009
Filed:
Jan. 18, 2007
Masaya Ichinose, Hitachiota, JP;
Shinya Oohara, Hitachi, JP;
Motoo Futami, Hitachiota, JP;
Yasuhiro Imazu, Hitachinaka, JP;
Masaya Ichinose, Hitachiota, JP;
Shinya Oohara, Hitachi, JP;
Motoo Futami, Hitachiota, JP;
Yasuhiro Imazu, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An excitation power converter of a doubly-fed generator is protected from excess current to be caused by ground fault or system disturbance and operation continuity of the power converter is ensured. In a power converter system, in order not to flow excess current generated in secondary windings of the doubly-fed generator into the power converter, a rectifier is connected in parallel to the power converter via a reactor, a DC link of the rectifier is connected to a DC link of the power converter, excess current flowing from the secondary windings is separately flowed at a reactor impedance ratio to reduce an amount of current flowing into the power converter, and a semiconductor switching element of an excess current generation arm of the power converter is set to an on-state.