Control system, electronically commutated motor system, draft inducer apparatus and method
US5075608A · kind A · utility
Inventors
Key dates
| Filing date | Feb 20, 1990 |
| Grant date | Dec 24, 1991 |
| Priority date | — |
| Expiry date | Feb 20, 2010 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B2600/021
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control system and method for an electronically commutated motor having a stationary assembly with a plurality of winding stages for carrying a motor current in response to application of a voltage having a magnitude subject to variations, the motor further having a rotatable assembly. The control system is adapted to receive control pulses having a duty cycle which is a function of a desired operating torque or speed for the motor. The control system and method are responsive to the motor current for generating a pluse width modulated (PWM) series of pulses having a pulse repetition rate having a duty cycle which is a function of the duty cycle of the control pulses. The PWM series of pulses are supplied to the commutating circuit as a pulsed signal whereby the operating torque or speed of the motor is a function of the duty cycle of the control pulses and is substantially independent of variations in the magnitude of the applied voltage. The control system may be part of a draft inducer apparatus or method for use with a combustion chamber having an exhaust outlet including a fan for moving air through the exhaust outlet and thereby to induce a draft in the combustion chamber. …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.