Thermostat with means for disabling PID control
US4991770A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1990 |
| Grant date | Feb 12, 1991 |
| Priority date | — |
| Expiry date | Mar 27, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D23/1906
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A thermostat is disclosed which includes a Proportional-Integral-Derivative (PID) controller and a means for disabling the PID controller for selected periods. The PID controller is disabled during a temperature recovery period, which can be triggered by the occurrence of one or more of many preselected events. The PID controller is re-enabled when the thermostat setpoint less a void offset temperature is reached. To reduce error in future temperature recovery periods, the void offset temperature is adjusted after a temperature recovery by adding the amount of error to the void offset temperature to create a new void offset temperature for use in a next temperature recovery period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.