Method of controlling the capacity of a transport refrigeration system
US4918932A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 24, 1989 |
| Grant date | Apr 24, 1990 |
| Priority date | — |
| Expiry date | May 24, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D23/20
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A method of controlling a refrigeration system by determining an average air temperature by sensing and averaging evaporator return and discharge air temperatures, and developing an average error by using the average air temperature and a selected set point temperature. The average air temperature is then used to calculate a proportional error and an integral error, and the discharge air temperature is used to calculate a floor error. The proportional error, integral error and floor error are weighted by predetermined gain factors and then summed to provide an error signal which is used to modulate the capacity of the refrigeration system, with the control mode depending upon the location of the error signal relative to set point.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.