Method and apparatus of reducing acoustic noise in switched reluctance electric motor
US5973462A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1998 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Mar 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P25/08
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A switched reluctance motor drive includes a noise reduction circuit configured to control the decay of current when a motor phase is switched from active to inactive. The current decay is controlled to occur in two stages: a first portion and a second portion. The first portion is controlled by alternately activating and deactivating one of the two switches in the two switch drive topology to obtain a current profile conforming to a predetermined profile. The current decay in the second portion of the inactive interval occurs by keeping both switches off so that it decays naturally. The duration of the first portion of the inactive interval is different for each motor phase, as is the duty cycle of the switch gating signal driving the switch that is alternately activated and deactivated. The scheme reduces the acoustic noise generated during operation of the motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.