An industrial design of 400 V-48 V, 98.2% peak efficient charger using E-mode GaN technology with wide operating ranges for xEV applications

This paper offers a wide-operating range electric vehicle charger design by employing an interleaved inductor-inductor-capacitor iL(2)C DC-DC converter. It uses two parallel (LC)-C-2 converters with 8-GaN switches on the primary side and a shared rectifier circuit on the secondary side, which it also enhances the circulating current, conduction losses, and current sharing. For iL(2)C converter, a constant voltage charging mode of operation is designed, also it proposes a hybrid control scheme of variable frequency + phase shift modulation (VFPSM). The entire concept is designed, simulated, and validated with a rated input voltage and load voltage of three different load conditions with converter line and load regulations are analyzed. To evaluate controller and converter performance, the idea is proven experimentally for variable load condition of full load, half load, light load with a rated input and output voltage of 400 V-in-48 V-0. In addition, line regulation is also performed and validated for wide input voltage application of 300 V-in-500 V-in with an output voltage of 48 V-0 at full load and peak efficiency of 98.2% is determined. Further, to provide the system effectiveness converter efficiencies are presented at various load operations from 3.3 kW to 330 W.