Ride-through method and system for HVAC&R chillers
US7332885B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 2006 |
| Grant date | Feb 19, 2008 |
| Priority date | — |
| Expiry date | Jun 7, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M5/458
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of providing ride-through capability in a chiller/refrigeration system employs a variable speed drive with an active converter stage, a DC link stage and an inverter stage for providing variable frequency and voltage to power at least one motor. An induction motor is coupled to the output of the inverter stage for driving a compressor in the chiller/refrigeration system. The ride-through method comprises operating the active converter to regulate the DC link voltage of the DC link stage to a predetermined voltage level until the current through the active converter equals a predetermined current limit, then transferring regulation of the DC link to the inverter upon reaching the current limit of the converter. The compressor is unloaded, and the power flow through the inverter is reversed to maintain the voltage level of the DC link stage. Pre-rotation vanes, slide valve, or check valve are used to unload the compressor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.