Magnetic sensor for switched reluctance motor
US5633546A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 30, 1993 |
| Grant date | May 27, 1997 |
| Priority date | — |
| Expiry date | Dec 30, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P25/0925
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Sensing apparatus for use on a polyphase switched reluctance motor (M, M'). The motor has a stator assembly (SA) and a rotor assembly (RA) including a rotor shaft (S) on which the rotor assembly is mounted for rotation with respect to the stator. Each respective motor phase is switched between active and inactive states by a commutator controller (C) responsive to sensed motor operating conditions. Switching a phase to its active state includes supplying current to the respective rotor phase windings, and switching the phase to its inactive state includes cessation of the current supply. Accordingly, there is a turn-on, running, and turn-off portion of each cycle of current supply with the turn-on portion of the cycle lasting approximately 30%-45% as long as the turn-off cycle. The apparatus includes a magnetic ring (10, 10') installed on the rotor shaft and rotatable therewith. It also includes a sensor (12, 14) for sensing changes in a magnetic field produced by the ring as it rotates with the shaft. The magnetic ring has a set of magnetic poles for each motor phase. The portion of the circumference of the ring subtended by one of the poles of each set is greater than that subten…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.