Brushless motor driving circuit and a method of controlling the brushless motor driving circuit
US6232730A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1999 |
| Grant date | May 15, 2001 |
| Priority date | — |
| Expiry date | Jun 2, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/21
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a brushless motor driving circuit of the invention, in the starting operation, an applying voltage is low and also the induced voltage is low, so that output values from sample and hold circuits 6 and 7 are substantially equal to each other. Thus, an output from a comparing circuit 10 is substantially equal to an output of a V/f converting circuit 11. As a result, the starting method which is identical with a conventional method is used. By contrast, when the number of rotation of a brushless motor 1 is increased, and the induced voltage is started to be observed, the condition is spontaneously shifted to that in which the driving voltage is automatically controlled at each time to an appropriate value for the number of rotation and the load of the motor. Accordingly, the switching operation from the starting control to the normal control is not required.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.