Nonlinear Predictive Control with Disturbance Observer for Induction Motor Drive

Abstract

A nonlinear predictive control (NPC) law with a disturbance observer is presented. It is applied to induction motor in order to track speed and flux profiles. The prediction defined on finite horizon is carried out via Taylor series expansion. The load torque is considered as an unknown disturbance and it is estimated by a nonlinear observer. Using the nonlinear predictive control has simplified the structure of the dynamic observer. The combination of the predictive controller and the observer works as a nonlinear controller with an integral action. The stability of the whole system can be achieved by simple design parameters. The simulations show very satisfactory performance of the proposed controller for trajectories tracking, the robustness to parameters variations and the disturbance rejection are successfully achieved