Control system, electronically commutated motor system, blower apparatus and methods
US4763347A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 17, 1987 |
| Grant date | Aug 9, 1988 |
| Priority date | — |
| Expiry date | Feb 17, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B2600/021
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Control system for an electronically commutated motor having a stationary assembly with a plurality of winding stages and further having a rotatable assembly. The control system is adapted to be supplied with an externally derived first pulse width modulated series of pulses having a first duty cycle which is subject to sudden changes which would cause a substantial inrush current to the motor if used directly for control purposes. The control system includes circuitry for generating a second series of pulses and modulating their width in response to the first series of pulses to produce a second pulse width modulated series of pulses that has a second duty cycle which varies less rapidly over time than the first duty cycle varies when the first duty cycle changes suddenly. Further included is circuitry for applying a voltage to one or more of the winding stages at a tine in accordance with the second pulse width modulated series of pulses and commutating the winding stages in a preselected sequence to rotate the rotatable assembly. In this way, inrush current to the motor is substantially reduced when the first duty cycle changes suddenly. Further control circuitry, electronically…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.