Method and apparatus for sequencing multistage systems of known relative capacities
US6540148B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 2001 |
| Grant date | Apr 1, 2003 |
| Priority date | — |
| Expiry date | Jul 27, 2021 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B2600/022
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
Disclosed is a method and apparatus for controlling multistage systems where the relative capacities (process gains) of each stage are known. The method uses a split-range control concept in order to control multiple stages with a single feedback controller, such as PID. Stage combinations are generated automatically and sequenced to provide contiguous control and optimum control resolution across the overall range of the multistage system. The control method incorporates hysteretic deadzones to improve robustness around stage transition points. The assumption of a tuned PI feedback controller allows the size of the deadzone to be related to general control performance requirements applicable across classes of similar systems. A simulated HVAC&R system is used to evaluate the method and it is compared an alternative approach.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.