Adaptive demagnetization compensation for a motor in an electric or partially electric motor vehicle
US6591925B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 17, 2001 |
| Grant date | Jul 15, 2003 |
| Priority date | — |
| Expiry date | Feb 8, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S903/91
- 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 (300). 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 (302). The controller produces an indication of magnetization based on the reference voltage, the detected permanent magnet induced voltage, and the predetermined speed. If the indication of magnetism reaches a predetermined threshold, the motor is made inoperable and/or a current to the motor is limited to prevent damage to components (306, 308, 310, 312, 314). Preferably, a user of the vehicle is made aware of these actions by an audible and/or visual indicator (308, 314). If available, another source of motive power is substituted for the motor that is made inoperable (316).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.