|Author's Email Address
||This thesis had been viewed 5571 times. Download 0 times.|
|Type of Document
||Design of Adaptive Nonlinear Controllers with Perturbation Estimation for Perturbed Systems in Semi-strict Feedback Form|
|Date of Defense
Lyapunov stability theorem
Semi-strict feedback form
Terminal backstepping control
Output feedback variable structure control
||In this dissertation three robust control strategies are proposed for nonlinear dynamic systems with matched and mismatched perturbations.|
Firstly, a new backstepping control scheme was proposed so that it can be directly applied to systems with unknown multiple time-varying delays for solving regulation problems. The delay terms in the dynamic equations can be nonlinear state functions in non-strict feedback form and the upper bounds of the time delays as well as their derivatives need not to be known beforehand. By utilizing adaptive mechanisms and derivative estimation algorithm to estimate the perturbations in the designing of backstepping controller, not only one can further alleviate the problem of ``explosion of complexity', i.e., reducing the number of time derivatives of virtual inputs that the designers have to compute in the design of the traditional backstepping controller, but also the designers do not need to know the upper bounds of perturbations as well as perturbation estimation errors in advance. Furthermore, the property of asymptotic stability is guaranteed.
Secondly, a nonsingular terminal adaptive backstepping control with perturbation estimation scheme was designed for a class of multi-input systems with matched and mismatched perturbations to solve regulation problems. The main advantage of this control scheme is that, without knowing the upper bounds of perturbations, the controlled system is still capable of suppressing the perturbations so that the controlled states are able to reach zero within a finite time. Another advantage is that there is no singular problem at all.
Thirdly, an adaptive terminal output feedback variable structure control (OFVSC) scheme was developed for a class of multi-input multi-output (MIMO) nonlinear systems with matched and mismatched perturbations. A perturbation estimation algorithm is utilized in designing the presented control scheme in order to overcome the problem of unmeasurable states. The resultant control system is capable of driving all the states into zero within a finite time and guaranteeing global stability. Several numerical examples and practical applications are demonstrated for showing the feasibility of the proposed control methodologies.
||Yon-Ping Chen - chair|
Yeong-Jeu Sun - co-chair
Jeang-Lin Chang - co-chair
Kuo-Kai Shyu - co-chair
Yon-Ping Chen - co-chair
Chih-Chiang Cheng - advisor
Indicate in-campus at 99 year and off-campus access at 99 year.|
|Date of Submission