AC Component-Based Control and Phase Shift Applications on Bidirectional Chopper With Auxiliary Full-Bridge Converter

This article proposes the supplementary application of ac component-based control to a bidirectional chopper with an auxiliary converter when the dc current flowing in the chopper is zero. The proposed chopper is composed of a bidirectional chopper as the main converter, an auxiliary converter with a single full-bridge converter, and an inductor, where phase shift is additionally applied to the carrier wave of the auxiliary converter. This setup is theoretically able to reduce the switching-ripple current to 1/4 of that the conventional bidirectional chopper, which consequently allows smaller inductor to be used in the chopper. Furthermore, experimental results using a 2 kW down-scaled model further verify the theoretical analysis results on the switching-ripple current, and the validity of the ac component-based control based on the steady- and transient-state performances of the proposed chopper, along with its coordination with the conventional dc component-based control. Finally, theoretical comparison with the conventional bidirectional chopper, three-level flying capacitor converter, and a bidirectional chopper with an auxiliary converter with no phase shift is done with respect to the inductor volume, power loss, and efficiency to verify the benefits of phase shift application in the proposed chopper.