Method of determining PID parameters and an automatic tuning controller using the method
US4754391A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 10, 1986 |
| Grant date | Jun 28, 1988 |
| Priority date | — |
| Expiry date | Sep 10, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B11/42
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A method of determining PID parameters for PID control by a PID controller having proportional, integral and derivative operating portions including the steps of monitoring a limit cycle generated in a controlled process to obtain characteristics of the process, continuing process control in a tuning mode where a nonlinear element is inserted preceding a proportional operation portion and at the same time an integral operation portion is connected in parallel to the series connection of the nonlinear element and the proportional operation portion and the derivative operation portion is removed from operation and determining optimum PID parameters to be used for succeeding process control on the basis of the results of the limit cycle monitoring. A controller utilizing the above method includes a nonlinear element, a switch for inserting the nonlinear element into a stage preceding the proportional operation portion and at the same time connecting the integral operation portion in parallel to the nonlinear element and the proportional operation portion so as to shift control into a tuning mode, a monitoring device for observing a limit cycle generated in the process in the tuning mo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.