SVPWM Strategy of Matrix Converter Fed Asymmetrical Six-phase Induction Motor With Common-mode Voltage Elimination and Unity Power-factor Operation

Asymmetrical six-phase induction machine (ASIM) with six balanced phases and two isolated neutral points require modulation in two orthogonal two-dimensional subspaces where one of them is associated with electromechanical energy transfer. Excitation of non-energy transferring subspace causes copper loss. Therefore, this paper proposes a novel space-vector based PWM strategy (SVPWM) of matrix converter (MC) fed ASIM where excitation in non-energy transferring plane is kept as zero and energy transferring plane is excited so as to generate ripple-free torque. Eighteen switching states of 3 phi-6 phi MC are used for this purpose which have zero common-mode voltage. Theoretical analysis shows that the input power-factor for this technique is same as the load power-factor. Finally, a new PWM strategy is proposed to operate the MC at unity power-factor at input. The proposed techniques are verified through simulations in Matlab and experiments on 3 kW hardware prototype.