Theoretical and experimental analysis for the RMS current ripple minimization in induction motor drives controlled by SVM technique

In this paper, an analytical approach useful for predicting the current ripple in induction motor drives controlled by spacevector modulation (SVM) technique is presented. The analysis is applied to determine the optimal modulation technique that minimizes the rms value of the current ripple. The minimization procedure is based on the analysis of the locus described by the current ripple in the (alpha)--(beta) reference frame. As a result, a simple equation has been obtained, which allows the online calculation of the optimal SVM switching pattern. It has been verified that it is possible to obtain a current ripple lower than that of symmetric modulation, and with a reduced number of commutations. Experimental results are provided to confirm the theoretical approach.