Traction motor current control apparatus
US4257092A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 1978 |
| Grant date | Mar 17, 1981 |
| Priority date | — |
| Expiry date | Dec 13, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/92
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A direct current motor power controlling chopper apparatus is disclosed which determines the operational speed of one or more traction motors propelling a passenger vehicle along a track. The speed of the motor is established by changing the ON and OFF conduction ratio or duty cycle relationship of a thyristor switch device to determine the field current and the armature voltage of that motor. The present apparatus can provide a greater controlled range of motor speeds including a lower minimum OFF operation and a full ON capacity. In addition, the present apparatus provides greater reliability due to less thermal stress on the thyristor switch devices and fewer circuit elements required to provide an improved motor current control operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.