Space Vector Pulse Width Modulation Scheme for Three to Seven Phase Direct Matrix Converter

In this paper a generalized multi-phase space vector theory is considered for developing the space vector modulation of a three-phase to seven-phase direct matrix converter (DMC). The modulation is based on the control of the voltage vectors in the first d-q plane, while imposing the remaining voltage vectors in the second and the third planes (x(1)-y(1), x(2)-y(2)) zero. The duty cycles of the bidirectional switches are obtained using space vector modulation theory. The output to input voltage transfer ratio is obtained as 0.7694 for unity input power factor operation. The proposed matrix converter system offers full control of the input power factor, no limitation on the output frequency range and nearly sinusoidal output voltage. The proposed space vector algorithm can be fully implemented on a digital platform. The theoretical analysis is confirmed by digital simulations which is further verified using experimental implementation.