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:
Jun. 03, 2003
Filed:
May. 04, 2001
Abbas Raftari, Northville, MI (US);
Vijay K. Garg, Canton, MI (US);
Ford Global Technologies, Inc., Dearborn, MI (US);
Abstract
A method and apparatus are provided for detecting the degradation of a permanent magnet in a motor of an electric or hybrid electric vehicle. A voltage monitor ( ) is directly coupled to a traction motor ( ) and/or generator motor ( ) to detect a permanent magnet induced voltage within the motor at a predetermined speed and no load condition ( ). A controller ( ) compares the detected permanent magnet induced voltage with an expected reference voltage that represents an expected permanent magnet induced voltage at full magnetization and the predetermined speed ( ). The controller produces an indication of magnetization based on the reference voltage, the detected permanent magnet induced voltage, and the predetermined speed. The indication of magnetization is stored for future reference ( ). Also, a safety indicator is produced for a user of the vehicle if the indication of magnetization is below a safety threshold.