Electronic expansion valve control for a refrigerant cooled variable frequency drive (VFD)
US6688124B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2002 |
| Grant date | Feb 10, 2004 |
| Priority date | — |
| Expiry date | Nov 7, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B30/70
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A control system for a refrigerant cooled variable frequency drive (VFD) for a chiller includes a controller which controls an electronic expansion valve to attempt to maintain a heat sink for the variable frequency drive within its design operating range. When the controller is unable to maintain the heat sink within its design operating range, a load on the chiller is reduced, either by reducing the frequency of the variable frequency drive, or if the chiller includes a compressor with internal guide vanes, by partially closing the guide vanes. The power rating of the VFD can thus be optimized based on its heat generating components operating at a controlled condition, unlike an air-cooled device which is dependent on the ambient environment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.