Gearless wheel motor drive system
US7592766B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2007 |
| Grant date | Sep 22, 2009 |
| Priority date | — |
| Expiry date | Dec 6, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T90/40
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
Methods and apparatus are provided for an electric vehicle embodying an axial flux traction motor directly coupled to a wheel thereof. The traction motor comprises a stator having coils for producing a magnetic field, an annular rotor magnetically coupled to the stator and mechanically to an output shaft. Permanent magnets of alternating polarity are mounted on the annular rotor. Magnetic shunts bridge a portion of the stator slots above the coils. The magnets are arranged in groups with group-to-group spacing exceeding magnet-to-magnet spacing. Adjacent edges of the magnets diverge. The method comprises, looking up d- and q-axis currents to provide the requested torque and motor speed for the available DC voltage, combining at least one of the d- and q-axis currents with a field weakening correction term, converting the result from synchronous to stationary frame and operating an inverter therewith to provide current to the coils of the motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.