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. 22, 1997
Filed:
Apr. 20, 1995
Nobuyoshi Mutoh, Katsuta, JP;
Taizou Miyazaki, Hitachi, JP;
Ryoso Masaki, Hitachi, JP;
Tsutomu Ohmae, Hitachi, JP;
Sanshiro Obara, Toukai-mura, JP;
Hitachi, Ltd., , JP;
Abstract
An electric vehicle torque controller has a torque calculating unit and an actual torque detecting unit. The calculated torque is compared with the actual torque to generate a torque compensation value, which is converted to a torque current signal. The torque current signal is used to generate a slip frequency, which is added to an output of an angular speed detector and used to set a secondary magnetic flux value. A secondary magnetic flux signal is generated according to the secondary magnetic flux value and the torque current signal. A secondary magnetic flux estimating unit generates an estimated secondary magnetic flux value, which is used to determine the exciting current. Primary motor current is controlled in response to the exciting current, the torque current, motor speed and slip value.