Current modulation motor controller
US5734248A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1997 |
| Grant date | Mar 31, 1998 |
| Priority date | — |
| Expiry date | Jun 6, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P27/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus for controlling the speed of an induction motor includes a first winding and a second winding. The first winding and second winding are adapted to be coupled to an AC source for supplying an AC input signal. A first switching device is coupled to the first winding and a second switching device is coupled to the second winding. Each of the switching devices is operative in a low impedance state enabling current to flow through the associated winding of each switching device and a high impedance state preventing significant current flow through the associated winding of each switching device. A controller switches each of the switching devices from the high impedance state to the low impedance state in a sequence for controlling the current in the windings, which induces a phase shift between the AC voltages across the windings.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.