Repetitive control strategy of SiC MOSFET to reduce EMI generation

Silicon carbide (SiC) MOSFETs benefiting from the wide bandgap materials offer a significant performance improvement compared with Silicon devices. However, the high switching speed makes the power switching to be a source of EMI. The suppression of the EMI generation can be achieved by shaping the switching transient to an “S-shape”. The active voltage control (AVC) strategy is a feasible method to achieve the S-shape by forcing the switching transient to follow a reference voltage. However some improvements need to be made in order to track the reference more accurately. This paper proposes a repetitive control strategy to control the switching transient of the SiC MOSFETs. A repetitive control loop is plugged in the original AVC system for a better accuracy of tracking the periodic reference. Finally, the simulation is made to verify the stability and accuracy of the proposed control system.