Power control for induction motors using variable frequency AC power
US7696715B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2006 |
| Grant date | Apr 13, 2010 |
| Priority date | — |
| Expiry date | Oct 14, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P27/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An autonomous controller allows an AC induction motor to operate over a broad range of AC power supply frequencies by reducing the amount of current supplied to the motor at lower frequencies. The controller detects the frequency of the power supply and switches the supply current on and off during each AC cycle to limit the RMS current to a value that is related to the detected frequency. Alternatively, the controller switches capacitive reactance into the power supply circuit which reduces the current supplied to the motor at lower AC frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.