Ferrite permanent magnet electrical machine and the application thereof within vehicle traction drives
US4651066A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 1984 |
| Grant date | Mar 17, 1987 |
| Priority date | — |
| Expiry date | Dec 12, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/70
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A drivetrain (48) for an electric passenger vehicle (10) includes a battery (40) for energizing a single-phase A.C. traction motor (18) which drives a ground engaging wheel (12) through a multi-speed transaxle (20). The motor is characterized by an external ferrite permanent magnet rotor (26) drivingly engaging an input shaft (32) of the transaxle. The motor is controlled by an inverter circuit (44) and a control circuit (46) which generates switch command signals to reciprocally actuate power transistors (56 and 62) within the inverter circuit as a function of operator demand, rotor position and rotor speed. The control circuit includes a motor positioning circuit (442) which toggles the motor current when the rotor speed falls below a predetermined level to dither the rotor about a park position for a predetermined period. A pre-start rotor positioner (224) is provided to mechanically lock the rotor in its park position to ensure the availability of a high electrical starting torque. Finally, a minimum starting speed circuit (599) provides for motor startup from other than the normal rotor park position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.