Method and apparatus for torque ripple reduction in sinusoidally excited brushless permanent magnet motors
US6380658B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 2000 |
| Grant date | Apr 30, 2002 |
| Priority date | — |
| Expiry date | Jul 14, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K29/03
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for determining a dimension in a motor is described. By applying Fourier analysis, a sequence of terms is obtained. Since the fifth harmonic is the most undesirable term, the minimization of the fifth harmonic term will make resultant waveform closer to sine wave. Based upon the above, a determination of an angle &dgr; is described, wherein the fifth harmonic term of the sequence of terms is minimized.An electric motor having a rotor and a set of slot on said rotor surface having a set of magnets with a width &dgr; along the circumference of said rotor surface is described. The width &dgr; is determined by a method that includes applying Fourier analysis thereby a sequence of terms is obtained. Since the fifth harmonic is the most undesirable term, the minimization of the fifth harmonic term will make resultant waveform closer to sine wave. Based upon the above, a determination of an angle &dgr; is described, wherein the fifth harmonic term of the sequence of terms is minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.