Apparatus for external inductance sensing for variable-reluctance motor commutation
US5661381A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 15, 1996 |
| Grant date | Aug 26, 1997 |
| Priority date | — |
| Expiry date | Feb 15, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P25/0925
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus for controlling commutation of a three-phase variable reluctance machine includes a sensor, a sampling circuit, an inductance waveform generating circuit, a phase advance circuit, a threshold signal generating circuit, and an output comparator. The sensor includes a stack of several laminations which are identical to the motor laminations that form the motor stator, and is mounted at one end thereof. The motor includes a plurality of stator windings forming a plurality of corresponding machine phases. The sensor also includes a plurality of sensor windings electrically isolated from the stator windings. Each sensor winding is associated with a corresponding stator winding. Each sensor winding also has an inductance characteristic that varies according to an actual position of the rotor. The sampling circuit is coupled to the sensor windings for selectably energizing at least one of the windings to generate a plurality of pulses indicative of the current passing through the energized sensor winding. The inductance waveform generating circuit includes a sample and hold device responsive to these pulses and outputs a generally sinusoidal signal indicative of an inductance…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.