Method and system for controlling an electric motor with variable switching frequency at variable operating speeds
US8456115B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2011 |
| Grant date | Jun 4, 2013 |
| Priority date | — |
| Expiry date | Dec 6, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A data processor establishes a first range of rotational speeds of a rotor of the motor from a first lower limit to a first higher limit and a second range of rotational speeds from a second lower limit to a second higher limit. A hysteresis band or a rotational range of speeds is established such that during operation in the first range the first higher limit is adjusted (e.g., raised by a first amount to be greater than the second lower limit). A sensor detects or measures a rotational speed of a rotor of the motor. The data processor determines whether the measured rotational speed falls within the first range or the second range, as adjusted by the hysteresis band, to identify a selected speed range. A switching frequency of a pulse-width modulation signal is varied in accordance with the selected speed range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.