The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 1998
Filed:
Apr. 18, 1995
Dale E Seborg, Santa Barbara, CA (US);
Yu-Ting Tina Miao, Alameda, GA (US);
The Regents of the University of California, Oakland, CA (US);
Abstract
Automatic detection of excessive oscillations in feedback control loops of a completely general nature can be achieved by generating an autocorrelation function of the controlled variable or control error in the control loop. From the pattern of the autocorrelation, a decay ratio which is a function of the depth of the first minimum and height of the first maximum of the oscillation in the autocorrelation function can be generated as a measure of the oscillation in the control loop. When the decay ratio exceeds a predetermined threshold, an alarm or report can be provided indicating that an excessive oscillation has occurred and to what degree. The source of the oscillation, that is whether it is within the monitored control loop or from a source external to the control loop can then be determined and the necessary remedy applied including a step input signal to the final control element in the control loop.