High-efficiency soft-switching PWM DC-DC converter for electric vehicle battery chargers

This paper proposes a high-efficiency softswitching dc-dc converter for electric vehicle battery chargers. All power switches achieve zero-voltage switching with the complementary pulsewidth modulation. Power switches can be actively-clamped with no increase in conduction losses. All output diodes achieve zero-current switching without any voltage oscillations. Thus, the proposed converter has a high-efficiency and compact structure. A charging strategy is also suggested. The battery charging controller is digitally implemented. The performance of the proposed converter is verified by experimental results for a 2.0 kW prototype circuit.