Carrier-Based Overmodulation Strategy for Matrix Converters

In this paper, carrier-based overmodulation for matrix converters is proposed. From the viewpoint of carrier-based modulation, there are two cases of overmodulation which correspond to (1) over output-voltage range and (2) over input-current range. Three simple strategies to limit the modulating functions under overmodulation are then studied. It is also clarified how the switching patterns and space vector utilization change in the overmodulation range. And the effects of the switching patterns and space-vector utilization on the current and voltage distortions are compared. Finally, the simulation results reveal that the error of fundamental amplitude between the output voltage and the desired output voltage is small with the so-called <2u1d>PWM, while using the max-input-phase as the reference in the carrier-based modulation gives low output voltage distortion.