Low and medium voltage PWM AC/DC power conversion method and apparatus
US5638263A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 1994 |
| Grant date | Jun 10, 1997 |
| Priority date | — |
| Expiry date | Dec 8, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/0043
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power supply apparatus and method for supplying direct current power to low and medium voltage DC loads wherein a multi-phase transformer having multiple secondary windings provides multi-phase power to multiple power cells, each of which have a single DC output and are controllable by a modulation controller. The primary and secondary windings in the power transformer may be star- or mesh-connected; the secondary windings may be shifted in phase. Because the power cells can be connected in series, the maximum output voltage for each cell may be less than the maximum line-to-line voltage. The power cell output can have variable DC voltage and current which can be controlled using pulse-width modulation techniques. AC input power is converted to DC output power for each power output line. Output power modulation can be produced by interdigitating a selected number of carrier signals so that harmonic components reflected back to the input are attenuated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.