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:
Jul. 27, 1993
Filed:
Jul. 20, 1992
Katsuji Marumoto, Hitachi, JP;
Kunio Miyashita, Hitachi, JP;
Kazuo Tahara, Hitachi, JP;
Keiichi Mashino, Katsuta, JP;
Atsushi Kanke, Hitachi, JP;
Akihiro Saito, Katsuta, JP;
Hitachi Ltd., Tokyo, JP;
Abstract
A control device for an electric generator for use with a vehicle engine includes an armature winding (stator) and a field winding (rotor) driven by the vehicle engine. A chopper is provided for controlling the field current of the field winding and a pulse width modulator is provided for controlling the duty cycle of the chopper in response to the operating conditions of the engine. A voltage feedback loop is provided from a normally provided battery which loop incorporates a detector for detecting the actual battery voltage and a comparator for comparing the battery voltage with a predetermined set voltage so that the difference in voltage is rendered to zero. The invention additionally provides a current feedback loop for controlling a deviation between a current command value determining the duty of the chopper and an actual current flowing through the field winding so as to be substantially zero. There is also disclosed means for adaptively modifying the current command signal and means for controlling the current demanded by the field winding to reduce the torque demanded by the generator at times, inter alia, of acceleration and engine knocking.