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Control And Disturbance Suppression Of Uncertain Port-Controlled Hamiltonian Systems

Posted on:2015-09-29Degree:DoctorType:Dissertation
Country:ChinaCandidate:L N JinFull Text:PDF
GTID:1228330428474787Subject:Control theory and control engineering
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The port controlled Hamiltonian (PCH) model is a powerful mathematical framework for modeling and controlling physical systems, not only emphasizing energy storage, dissipation, interconnection structure of physical systems, but also the motivation of physical systems based on passive control. However, there are perturbations including parameter uncertainties within the PCH systems, modeling errors and unknown external disturbances. These perturbations can lead the closed-loop system to the undesired way. Adaptive control and integral control can improve the robustness of the control system. Conventional control methods are infinite time asymptotic stable, the PCH systems with finite time control can reach and stay in the equilibrium state in finite time. The main work and research results in this thesis are summarized as follows:Firstly, consider the PCH system, adaptive control is used to compensate for control errors that are caused by unknown or uncertain parameter values of a system. In the case that the system is zero-state detectable or non zero-state detectable, the adaptive control is also combined with canonical transformation theory or feedback control for PCH systems. This allows for the adaptive control to be applied on the target zero-state detectable extended PCH systems in the port-Hamiltonian framework. This thesis focuses on the parameter perturbation of permanent magnet synchronous motor which causes the drift of equilibrium points. An adaptation law is introduced to ensure the stability even the Lyapunov function involves parameter perturbation and make the system follow the changed equilibrium.Secondly, in the presence of modeling errors and unknown disturbances, a technique that provides closed loop integral action depending on either matched disturbances or non-matched disturbances of PCH systems is already available. By coordinate transformation, regulation of passive outputs with matched disturbance of extended target PCH systems can be easily achieved with an integral control. Robustness of control systems can be increased by adaptive or integral control. While the presence of both parameter uncertainty and the unknown constant disturbance, the use of integral adaptive control can reach stabilization at the equilibrium point of the system. An integral adaptive control scheme of permanent magnet synchronous motor (PMSM) is presented in the PCH framework. The new approach is applied to design speed regulation controllers for the PMSM. Compensation for control errors and asymptotic rejection of unknown piecewise constant load torques are formally proved.Thirdly this thesis studies the finite-time terminal sliding mode (TSM) and PCH control theory. A fractional power form controller is designed with finite time convergence to the desired equilibrium. Through choosing different energy functions for port Hamiltonian systems, finite-time stability criterion and the energy shaping plus damping injection technique, the finite-time stabilization problem is investigated for the PCH systems. The finite-time control scheme for speed regulation of PMSM is investigated under PCH, TSM and fast TSM stabilization theory. Finite-time TSM and fast TSM controllers are designed respectively, and the finite-time stability of the desired equilibrium point is also achieved under the PCH framework.Finally, future work is provided based on the conclusion of whole work.
Keywords/Search Tags:Port-Controlled Hamiltonian System, Adaptive Control, IntegralControl, Finite Time Control, PMSM
PDF Full Text Request
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