Circuit and method for the actuation of a brushless DC motor
US5767641A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1997 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Feb 25, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P2209/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit and a method for actuating a brushless DC motor are proposed. The circuit comprises a delta-connected oscillator (1) for generating a triangular voltage as a function of commutation pulses resulting from the position of the rotor of the DC motor, a sampling and hold circuit (2) for sampling and holding a holding voltage (Ul) from the curve of the triangular voltage as a function of time at the moment of the commutation, and a differential amplifier (4) for amplifying the differential voltage between the triangular voltage and the holding voltage (Ul), with the output signal of the differential amplifier being supplied to the final stage of the actuation control circuit. An additional adder (3) for adding a voltage (U block) to the holding voltage (Ul) sampled from the triangular voltage and held can be used, with the differential voltage between the triangular voltage and the sum of holding voltage (Ul) and block voltage (U block) being amplified in the differential amplifier (4). Thus, the method is characterized in that in the actuating signal the steepness of the slopes is set by varying the amplification of a differential amplifier (4) and/or the length of the blocks …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.