Comprehensive Robust and Fast Control of $Z$-Source-Inverter-Based Interior Permanent Magnet Synchronous Motor Drive System

Abstract

This article aims to facilitate the practical use of Z-source inverters in motor drive systems due to their outstanding properties. To this end, a robust and fast control scheme with two possible configurations for a permanent magnet synchronous motor (PMSM) drive system using a Z-source inverter is presented. In this article, the proposed control system is applied to the speed and current loops in the motor side as well as the current and voltage loops in the Z-source side. The idea is to combine the features of sliding-mode control as the feedback controller (basic configuration) with a disturbance attenuation technique as a feedforward compensator (enhanced configuration), linking with a newly modified space vector modulator. The disturbances and uncertainties associated with practical PMSM drive systems and Z-source inverters are inherently time varying and introduce high bandwidth characteristics. Hence, the proposed closed-loop control structure provides the following features to the system: 1) high robustness to external disturbances and parameter variations; 2) fast transient response during large and abrupt load changes; and 3) reduced ripple in delivered torque of the motor. In addition, a systematic design procedure for determining the values of the control parameters is presented. The theoretical analyses are validated by experimental tests in a laboratory setup. The results prove the robustness of the enhanced configuration, with a 25% reduction in torque ripple and 60% in settling time. Furthermore, compared to the previous space vector modulation technique, the proposed technique gives a 40% reduction.