Method and apparatus for controlling a DC to AC inverter system by a plurality of pulse-width modulated pulse trains
US5625539A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 1995 |
| Grant date | Apr 29, 1997 |
| Priority date | — |
| Expiry date | May 10, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M7/4807
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A pulse train pulse-width modulated by PWM control using a sine-wave signal and a carrier signal is inverted alternately in positive-negative polarity. With a high-frequency AC signal obtained by the inversion, a primary side of a transformer for insulating input and output from each other is excited. This arrangement makes it possible to employ a high-frequency transformer which has a capacity ratio of about 1/30 and a weight ratio of about 1/20 relative to a commercial-frequency transformer, instead of using it. Thus, an inverter apparatus can be reduced in size and weight as compared with the system using the power-frequency transformer. A sine-wave AC waveform with substantially less distortion similar to the waveform output by the conventional PWM control can be obtained with a simple construction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.