Variable speed control apparatus for induction motor
US4099108A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1976 |
| Grant date | Jul 4, 1978 |
| Priority date | — |
| Expiry date | Aug 20, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P2201/03
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An induction motor is operated by a power supply of variable voltage and variable frequency. The voltage and frequency of the variable-voltage variable-frequency power supply is changed by a control circuit to accelerate or decelerate the induction motor. For slowly controlling the speed of the induction motor, the ratio of the output voltage to the output frequency of the variable-voltage variable-frequency power supply is maintained substantially constant. The control circuit includes a voltage correcting means which, in response to a command for sudden acceleration or deceleration of the speed of the motor, corrects the output voltage of the power supply in accordance with the acceleration or deceleration rate and the prevailing magnitude of the output frequency of the variable-voltage variable-frequency power supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.