Variable speed drive
US9024559B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 2010 |
| Grant date | May 5, 2015 |
| Priority date | — |
| Expiry date | Nov 29, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/163
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A converter module for a variable speed drive having a semiconductor device for precharge is described. The precharge circuit includes switching modules, one switching module with a first semiconductor switch connected in parallel or series with a second semiconductor switch. The second semiconductor switch is switched on and off during the precharge operation in order to limit the inrush current into the DC Link. After the precharge operation, the second semiconductor switch is turned on all the time and acts like a diode. The second semiconductor device may have a lower maximum current rating than the main semi-conductor devices. The lower current rated semiconductor device experience the same short circuit current as the higher current rated semiconductor device. The lower current rated semiconductor device can be supplied with a larger gate to emitter voltage than the higher current rated semiconductor device to equalize current between semiconductor devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.