Single-Stage Totem-Pole ACDC Converter Based on Boost Half-Bridge Structure for Battery Chargers

In this article, a new single-stage bridgeless totempole ac-dc converter is proposed. The proposed converter is composed of two single-stage boost half-bridge ac-dc converters with the interleaved operation. Besides, while preserving the advantages of the L-type half-bridge-based single-stage totem-pole ac-dc converter, the proposed converter has the ability of phase-shedding operation, which helps to increase the total efficiency of the converter due to reduced switching and core losses by half under medium and light loads. A hybrid harmonic injection in phase shift and duty cycle according to battery voltage is proposed, which not only improves total harmonic distortion to smaller than 4% under the whole load range but also extends the zero-voltage switching range of the converter under a wide voltage range. The proposed control method can be utilized in the general dual-active-bridge-based single-stage converter. Experimental results from a 1.5-kW prototype are provided to validate the proposed concepts.