Method and apparatus for driving a DC motor
US7592764B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 2, 2008 |
| Grant date | Sep 22, 2009 |
| Priority date | — |
| Expiry date | Jan 2, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit for determining a direction of rotation of an electric motor, the motor having asymmetry and/or eccentricity in a profile of back electromotive force as a function of angular position of a rotor with respect to a stator, the circuit receiving a signal representing the BEMF, and use the corresponding asymmetry and/or eccentricity in the signal to derive the direction of rotation. The signal representing the back emf can be generated by a control circuit. The control circuit can have a feedback loop regulator to generate a control signal (TL or TR) to control a current drive circuit (11,12) to control an amplitude of current (iw) in the windings, the feedback loop regulator being arranged to compare the amplitude of the current (iw) in the windings with a reference value (iset), and use the control signal to provide the signal representing the back electromotive force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.