An Advanced Control Strategy for Bidirectional Isolated Three Phase AC/DC Dual-Active-Bridge Converter in Hybrid Microgrid

This paper proposes an advanced control strategy consisting of current stress optimization based on triple-phase-shifting (TPS) modulation for front-end DAB converter and 33% PWM method for back-end three-phase full bridge inverter. Compared with the traditional phase shift control, the control strategy proposed for the front-end DAB converter achieves linear control and significantly reduces current stress. In addition, it reduces the DC-Link capacitance, which improves the safety of the equipment. The 33% modulation method adopted by the full bridge inverter at the back-end reduces the switching loss of semiconductor devices. The principle, derivation and realization of the proposed control strategy are described in detail. Simulation results are presented to validate the effectiveness of the proposed strategy.