Circuit for controlling brushless DC motor
US5777448A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 23, 1996 |
| Grant date | Jul 7, 1998 |
| Priority date | — |
| Expiry date | Aug 23, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit controls a brushless DC motor having a magnetic rotor and a stator coil. The circuit has a switching element for switching a current to the stator coil to rotate the rotor. The circuit compares a voltage induced in the motor with a neutral voltage of a DC power source with no delay to provide a positional detection signal. The circuit has a one-chip microcomputer for examining a PWM waveform signal used to generate a synchronous signal and the switching timing of the switching element. The microcomputer samples the positional detection signal only during intervals in which a current is supplied to the stator coil, and carries out other processes during intervals in which no current is supplied to the stator coil.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.