Novel current balancing method for HF interleaved converters with reduced control effort

The Active Neutral Point Clamped (ANPC) topology as a three level inverter is particularly well suited for subdivision into fundamental switching semiconductors and modulating fast switching semiconductors. This allows each semiconductor to be selected for its best characteristics. One part of a hybrid ANPC inverter can be realized with high frequency interleaved stages based on wide bandgap power semiconductors. A challenge is the calculation effort of the duty cycle for this high switching frequency, especially due to the interleaved based stages. It is often considered that the reduction of the calculation effort has a negative impact on the current accounting. This paper proposes a simplified method for the balancing of the current in the interleaved stages with significantly reduced control frequency. An active current symmetry should be implemented, which would be easier due to the reduced control effort. In this paper, this method is experimentally validated without active current symmetry control.