Thermal protection for AC traction motors using temperature estimations to calculate torque limits and blower speed requirements
US5446362A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 21, 1994 |
| Grant date | Aug 29, 1995 |
| Priority date | — |
| Expiry date | Jun 21, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/64
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A thermal protection apparatus for an AC traction motor including a stator, a rotor, a blower fan, and an inverter includes measuring apparatus for measuring ambient air temperature of the motor and atmospheric air pressure of the motor. A computer is provided for using the measured ambient air temperature and atmospheric air pressure values for estimating a plurality of temperatures in the AC traction motor and for calculating a plurality of motor torque limits imposed by the plurality of estimated temperatures. A control system is provided for controlling the inverter by providing a signal comprising the lowest of the calculated plurality of motor torque limits to an inverter controller. The control system can also be used to calculate a plurality of blower speed requirements imposed by the plurality of estimated temperatures and set the blower speed of the motor to the highest of the calculated plurality of blower speed requirements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.