Half-bridge converter based on switched-capacitor resonance without using deadtime control for automotive applications

Abstract

For virtually all converters and inverters, it is necessary to take care of shot-through and deadtime in the half-bridge subcircuits. Floating gate drive designs are also needed. The additional cost to realise these features becomes a concern in low power applications. This study presents a centre-tapped inductor method added to the bridge to satisfy these constraints cost-effectively. The shoot-through current is under controlled. Using push-pull P and N channel metal-oxide silicon field-effect transistors, the floating or level-shift gate drive can be eliminated and the converter becomes simple. The proposed method has been successfully applied to switched capacitor resonant converter. Formulations of the overlapping and resonant equations have also been developed. It is found that the current in the centre-tapped inductor can be transferred to the resonant inductor with the proposed circuitry with no additional loss involved in the design. Moreover, all the current is under zero-current switching. The design has been validated experimentally and high efficiency is realised using the proposed design.