Harmonic burst mode control strategy for full-bridge series resonant convertersfor electric vehicles application

An effective output voltage regulation method using harmonic burst mode control strategy is presented. By using this strategy, the operating performance of the full-bridge series resonant dc-dc converter (SRC) applied to electric vehicle (EV) battery charging is improved. The proposed control strategy not only performs load regulation, but it also achieves soft switch both at turn-on and turn-off under any load condition. It also improves the system efficiency over 10% for light load conditions compared to the traditional frequency modulation control method, without adding extra hardware. Theoretical, compensation and loss analysis are discussed in details along this paper. Experimental results based on a 1-kW prototype with 20 cm air gap between the primary and secondary side of the SRC converter are presented to demonstrate the effectiveness of the proposed control strategy.