3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item An automatic controller tuning algorithm.(1991) Christodoulou, Michael, A.The report describes the design of an algorithm which can be used for automatic controller tuning purposes. It uses an on-line parameter estimator and a pole assignrnent design method. The resulting control law is formulated to approximate a proportional-integral (PI) industrial controller. The development ofthe algorithm is based on the delta-operator, Some implementation aspects such as covariance resetting, dead zone, and signal conditioning are also discussed. Robust stability and performance are two issues that govern the design approach. Additionally transient and steady state system response criteria are utilized from the time and frequency domains. The design work is substantiated with the use of simulation and real plant tests.Item Adaptive control and parameter identification(2015-07-02) Rabinowitz, Basil PThe broad theory of adaptive control is introduced, with m o t i v a t i o n for using such techniques. The two mos t popu l a r techniques, the Model Re f er e n c e A d a ptive C o n t r o l l e r s (MRAC) and the Self Tuning C o n t r o l l e r s (STC) are studied in more d e t a i l . The MRAC and the STC often lead to identical solutions. The c on d i t i o n s for which these two techni q u e s are e q u i v a l e n t are discussed. P a r a m e t e r Adap t a ti o n A l go r i t h m s (PAA) are required by both the MRA a n : the STC. For this reason the PAA is e x a m i ne d in some det.ai . This is i n itiated by de r i v i ng an o f f - l i n e lea; -squares PAA. This is then c o n v e r t e d into a r ec u r s i v e on-l in e estimator. Using intuitive arguments, the various choices of gain p a r a m e t e r as well as the v a r ia t i o n s of the nasic form o f the a l g o r i t h m are discussed. This i n c l ud e s a w a r n in g as to w here the p i tf a l l s of such a l g o r i t h m s may lie. In order to examine the s t a b il i t y of these a lgorithms, the H y p e r s t a b i l i t y theorem is introduced. This requires k n o w l e d g e of the Popov i n e q ua l i t y and Stric t l y P o s itive Real (SPR) functions. This is intro d u c ed initially using i n t u i t i v e ene i g y concepts after which the r i g o r ou s m a t h e m a t i c a l representa* ion is d e r i v e d . The H y p e r s t a b i l i t y T h e o r e m is then used to exam i n e the s t a b i l i t y condition for various forms of the PAA.