Patent · US Expired

Detection of demagnetization in a motor in an electric or partially electric motor vehicle

US6720792B2 · kind B2 · utility

9Cited by
9References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 17, 2001
Grant dateApr 13, 2004
Priority date
Expiry dateJan 16, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S903/906
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

In an electric or hybrid electric vehicle, a voltage monitor (102) is directly coupled to a traction motor (38) and/or generator motor (30) to detect a permanent magnet induced voltage within the motor at a predetermined speed and no load condition. A controller (100) 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 comparison includes identifying points of synchronization and using those points to determine a difference in the detected permanent magnet induced voltage that is caused by a faulty component.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.