LPV $\mathcal {H}_\infty$ Control with Disturbance Estimation for Permanent Magnet Synchronous Motors

Abstract

This paper presents an $\mathcal {H}_\infty$ controller with an $\mathcal {H}_\infty$ state estimator using a linear parameter-varying (LPV) model of permanent magnet synchronous motor (PMSM). The proposed control method comprises a nonlinear torque modulation, an LPV $\mathcal {H}_\infty$ state estimator, and an LPV $\mathcal {H}_\infty$ state feedback controller. The use of nonlinear torque modulation enables formulation of the electromechanical dynamics of the PMSM in the form of an LPV system. The LPV $\mathcal {H}_\infty$ state estimator is designed to estimate the velocity, currents, and disturbance based solely on position measurement. We introduce a vertex expansion technique to cover all operating points of an LPV system. A velocity tracking controller is designed in the frame work of $\mathcal {H}_\infty$ control to be robust against disturbance. The proposed controller was implemented and validated with a motor generator set consisting of two PMSMs. Experimental results are presented to validate the effectiveness of the proposed method compared to conventional field-oriented control. These results show improved transient responses to velocity reference in the presence of disturbance.