Hybrid-Switching Full-Bridge DC–DC Converter With Minimal Voltage Stress of Bridge Rectifier, Reduced Circulating Losses, and Filter Requirement for Electric Vehicle Battery Chargers

Abstract

This paper first presents a hybrid-switching stepdown dc-dc converter, and then, by introducing transformer isolation, a novel hybrid-switching phase-shift full-bridge dc-dc converter is derived for electric vehicle battery chargers. The proposed converter provides wide zero-voltage-switching range in the leading-leg switches, achieves zero-current-switching for lagging-leg switches, and uses a hybrid-switching method to avoid freewheeling circulating losses in the primary side. Because the resonant capacitor voltage of the hybrid-switching circuit is applied between the bridge rectifier and the output inductor for the duration of the freewheeling intervals, a smaller sized output inductor can be utilized. With the current rectifier diode of the hybrid-switching circuit providing a clamping path, the voltage overshoots that arise during the turn-off of the rectifier diodes are eliminated and the voltage stress of bridge rectifier is clamped to the minimal achievable value, which is equal to secondary-reflected input voltage of the transformer. The inductive energy stored in the output inductor and the capacitive energy stored in the resonant capacitor of the hybrid-switching circuit are transferred to the output simultaneously during the freewheeling intervals with only one diode in series in the current path, achieving more effective and efficient energy transfer. The effectiveness of the proposed converter was experimentally verified using a 3.6-kW prototype circuit designed for electric vehicle onboard chargers. Experimental results of the hardware prototype show that the converter achieves a peak efficiency of 98.1% and high system efficiencies over wide output voltage and power ranges.Index Terms-Hybrid-switching method, phase-shift full-bridge dc-dc converter, plug-in electric vehicle battery charger, zerocurrent-switching, zero-voltage-switching.

Hybrid Sinusoidal-Pulse Charging Method for the Li-Ion Batteries in Electric Vehicle Applications Based on AC Impedance Analysis

“…5: ( ) 1 0 0 3 1 2 3 3 2 2 3 2 3 1 3 2 1 2 1 1 3 3 1 1 In section IV, the average charging current and fundamental wave have been derived by equation (13) and (14), respectively. The root-mean-square value of the charging current is derived as (15). …”

“…Numerous assessments have been carried out to improve the charger efficiency through soft switching [14], [15], auxiliary circuits [16], hybrid topology, etc. [17].…”

A Dual Half-Bridge Converter with Adaptive Energy Storage to Achieve ZVS over Full Range of Operation Conditions

“…However, the auxiliary circuits lead to higher circulation current and more conduction loss. The zero-voltage and zero-current-switching (ZVZCS) full-bridge converters are another solution to the problems [11][12][13][14]. In these converters, metal-oxide-silicon field-effect transistors (MOSFETs) as leading-leg switches are turned on with ZVS, while insulated gate bipolar translators (IGBTs) as lagging-lag switches are turned off with ZCS.…”

A High-efficiency Method to Suppress Transformer Core Imbalance in Digitally Controlled Phase-shifted Full-bridge Converter

“…Phase-shifted full-bridge (PSFB) converter is extensively used in medium-power and high-power applications because of its advantages of high efficiency and low electric stress on power devices at the same power level [1]- [4]. Operating in the first and third quadrants of the B-H curve is an outstanding characteristic of PSFB converters, but easily leads to transformer core imbalance.…”