Performance evaluation of Two-level to Three-level Three-phase Dual Active Bridge (2L-3L DAB3)

The paper presents the performance evaluation of the bidirectional two-level to three-level three-phase Dual Active Bridge (2L-3L DAB3) topology. A three-phase three-level neutral point clamped (NPC) topology is implemented for the secondary bridge which enables semiconductor switches to be operated at higher DC bus voltage. Different operating modes of the topology with analytical models describing the current and voltage waveforms are presented. Further, analysis of power transferred, RMS currents, transformer utilization factor, and soft-switching capabilities against the control parameters is investigated. Experimental results of a hardware prototype are included to validate the presented analysis and model.