Analysis of Current Error Space Phasor for a Space Vector Modulated Indirect Matrix Converter

Abstract

AC motor drives fed from current controlled power electronic converters are popular on account of their superior steady-state and transient performance. Hysteresis control is a popular current control technique, which needs modifications to compensate for its demerits. Appraisal of current error as a space phasor for implementing the hysteresis controller is one such modification. Current Error Space Phasor (CESP) based hysteresis controller for VSI fed motor drives are capable of achieving superior dynamic performance. With the modified hysteresis current controller, the drive operates at a constant switching frequency and ensures an optimal switching vector selection. This article presents the analysis of CESP for a space vector modulated Indirect Matrix Converter (IMC). The modified algorithm for Space Vector Modulation (SVM) of IMC accommodates for the variations in DC link voltage since CESP is input voltage dependent. The boundary for the hysteresis current controller is calculated from the computed values of CESP. The time-varying nature of the hysteresis boundary ensures a constant switching frequency operation for IMC. Thus, a CESP based hysteresis controller is proposed for the vector control of the IMC fed PMSM drive. Experimental results are presented for validating the performance of the proposed controller.