Tuning methods for fractional-order controllers
US7599752B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 17, 2006 |
| Grant date | Oct 6, 2009 |
| Priority date | — |
| Expiry date | Mar 10, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B13/024
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A method for tuning a fractional-order proportional-integral (PI) controllerincludes deriving values for Kp, Ki, and α that satisfy a flat phase condition represented byKp is derived to ensure that a sensitivity circle tangentially touches a Nyquist curve on a flat phase. Ki and α are derived to ensure that a slope of a Nyquist curve is approximately equal to the phase of an open loop system at a given frequency. A method for tuning a PI controllerwhere the gain crossover frequency wc is known includes obtaining measurements of ∠P(jwc) and |P(jwc)| of an unknown, stable real plant P(s) using iterative relay feedback tests, and approximating the derivative of the plant phase, ∠P(jwc), provided by the relationshipwherein |Kg|=P(0) is the static gain of the real plant P(s).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.