An SVD-based SVM with common-mode voltage reduction for direct matrix converters

In this paper, a new space vector modulation (SVM) strategy is presented to reduce the output common-mode voltage (CMV) for direct matrix converters. This method modifies the traditional singular value decomposition modulation to enable the usage of switch vectors with 120° phase shift, then substitutes two of the corresponding switch states by an orientation switch state which connects every input to one output phase. Since those orientation switch states have zero CMV at the output side of matrix converters, by this mean, not only the peak value but also the voltage transitions of the CMV are decreased dramatically. Besides, the improvement of the modulation can be implemented by some minor modification in software, and thus not additional costs in hardware are needed. Simulation results are shown to corroborate the effectiveness of the proposed method.