An Overmodulation Strategy for Matrix Converter Under Unbalanced Input Voltages

In this article, an improved space vector pulsewidth modulation strategy for matrix converter is proposed under unbalanced input voltages. First, to obtain the higher output voltage, two novel space vector pulsewidth modulation strategies based on the linear superimposition principle are presented by modifying the magnitude of the reference output voltage and the reference input current vectors. Second, in order to evaluate the performance of the proposed strategy, the harmonic characteristics of the input currents and output voltages are quantitatively analyzed by employing the double Fourier integral transform method. The novelty of this article lies not only in the modification of a conventional space vector pulsewidth modulation strategy for a higher output voltage under unbalanced input voltages, but also in a quantitative analysis that accurately evaluates the overmodulation performance with input unbalance using the double Fourier integral transform approach. Finally, the performance of the proposed strategy and the correctness of the harmonic analysis method are verified by the comprehensive simulation and experimental results for matrix converters.