This project deals with the development of a high performance nonlinear predictive control permanent magnet synchronous motor (PMSM) drive. The objective of the controller is to track the imposed speed profile while regulating the d-axis current. The research work is directed towards improving trajectory tracking capability, stability guarantee, constraints respecting, robustness to parameters variations and disturbance rejection.;The other derived nonlinear predictive law is specified by optimizing a newly defined design cost function. A key feature of the proposed control is that the information about the external perturbation and parameter uncertainties is not needed to enhance the robustness, and a zero steady state error is guaranteed by an integral action which arises naturally in the controller. Here, an anti-windup compensator based on the well known conditional integral method is proposed when the actuator saturations are incorporated in the controller. The stability of the proposed approach is carefully investigated and the stability of closed-loop system has been established using Lyapunov Theory. It is shown that under a mild condition, zero tracking error can be achieved under the proposed scheme.;The validity of the proposed control strategy is experimentally tested on a dSPACE OS1104 Board driving a 0.25-kW PMSM drive. Satisfactory results are obtained regarding trajectory tracking, disturbance rejection and constraints respecting.;The main part of nonlinear predictive control is the system behavior prediction model. The prediction model is obtained by using the Taylor series expansion. However, it's known that the nonlinear predictive control based on the Taylor series expansion, cannot remove completely the steady state error under mismatched parameters and external perturbation. To this end, two types of control algorithms are proposed in this work. First, the nonlinear predictive controller is enhanced by embedding a disturbance observer, which behaves like a PID or PI speed controller according to the relative degree of the speed output. The nonlinear disturbance observer is specified by using a newly defined design function due to the fact that the existing disturbance observer based control technique is limited to systems having the same input and disturbance relative degrees while, for a PMSM, the load torque relative degree is less than the input's one. The closed loop system under the disturbance observer works as a nonlinear controller with an integral action. Consequently, when the control saturates due to the natural physical limitation, the integral part may cause highly oscillations to appear or, even worse, may cause the system to be instable. This phenomenon occurs especially, when large set-point changes are made. To suppress this undesired side effect known as integrator windup, an anti-windup compensator is derived readily by using the actuator saturations in the observer synthesis.
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