Brushless motor control circuit
US5182500A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 26, 1991 |
| Grant date | Jan 26, 1993 |
| Priority date | — |
| Expiry date | Apr 26, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
According to the present invention, control is performed to set a constant difference between two phase inputs among three phase inputs to a three-phase brushless motor. As a result, imbalance between the respective phase inputs (signals) is eliminated, thus performing motor control with good rotational precision. According to the present invention, amplifiers (1.sub.1 -1.sub.3, 2.sub.1 -2.sub.3, 3.sub.1 -3.sub.3) for receiving rotor position detection signals of the motor are provided in common to the three-phase input lines of the three-phase brushless motor. One of the difference and the sum of a product of two phases signals, among three phase outputs from these amplifiers, and a signal as the square of the remaining phase signal is compared with a constant value. A comparison result signal is fed back to the amplifiers (1.sub.1 -1.sub.3, or 2.sub.1 -2.sub.3, or 3.sub.1 -3.sub.3) of a common stage of the three-phase input lines to control the rotation of the motor. The product of the two phase signals is obtained by a multiplier (11). The square of the remaining one phase signal is obtained by a square multiplier (12). One of the sum and the difference of the product and the sq…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.