The control strategy for a four-leg indirect matrix converter with unbalanced load

In this paper, a control strategy for a four-leg indirect matrix converter under unbalanced load condition is described. The four-leg indirect matrix converter can synthesise any desired three-phase line-to-neutral voltage. In order to obtain the reference output voltage under unbalanced load condition, the control strategy for four-leg indirect matrix converter is based on the decomposition of the output voltages and currents into positive, negative and zero sequence components. The classical proportional-integral (PI) controllers are applied to control the d, q components in synchronously rotating frame in all three sequences. In this paper, a carrier-based PWM is also introduced to generate PWM signals because this method is easily to implement compared with SVPWM method. Finally, simulation results are shown to verify the feasibility of proposed control scheme.