Low-noise operation of a machine fed by a pulse inverter
US5625542A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 24, 1995 |
| Grant date | Apr 29, 1997 |
| Priority date | — |
| Expiry date | May 24, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M7/5395
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for the low noise operation of a electrical machine driven by a pulse inverter computes the amplitudes and frequencies of the harmonics of the inverter output voltages. Through targeted setting of the modulation parameters, the frequency spectrum or the noise spectrum can be fanned out and harmonics, which would excite stator resonances, can be eliminated. Due to the independence of the modulation parameters from the modulation index (a.sub.0) and the fundamental oscillation frequency (f.sub.1), the fanning-out and the elimination has no influence on the fundamental oscillation (u.sub.GS) or on the operating point of the machine. The inverter is controlled through sinusoidal pulse width modulation (PWM) and sinusoidal pulse frequency modulation (PFM) of a triangular carrier signal (U.sub.H). By this method, the main groups of the harmonics with two ordinate numbers (n, v) are fanned out into subgroups with three ordinate numbers (n, m, v). In addition to a more uniform distribution, there also is a reduction in the amplitudes of the harmonics (U.sub.nmv) through this fanning-out method. The generated noise is reduced in level and the sound pattern does not co…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.