Method for controlling variable speed drive with chiller equipped with multiple compressors
US6370888B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 31, 2000 |
| Grant date | Apr 16, 2002 |
| Priority date | — |
| Expiry date | Aug 31, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B30/70
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
The invention uses a variable speed drive (VSD) only on a range of capacities corresponding from zero to standard point conditions, and if conditions correspond to higher than rated point current, the VSD is disconnected and the compressor is connected directly on line. This approach allows using a smaller size VSD. At the same time, if there are several compressors operating in the same machine, only one VSD is needed. The VSD drives a first compressor from zero to the speed corresponding to the line frequency. Controls then switch the first compressor to direct on line (DOL) and disconnects the VSD from the first compressor. The VSD is then available to drive a second compressor. This process can be repeated through multiple compressors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.