A Modulation Scheme for Differential-Mode ZVS Resonant-Switched-Capacitor Rectifier

This article proposes a predictive modulation scheme for a differential mode resonant switched capacitor rectifier (DMRSCR) to achieve high efficiency and power factor correction (PFC) for wide voltage gain. The modulation scheme ensures extensive zero-voltage switching (ZVS) turn-<sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> on all the switches under varying sinusoidal input voltage without requiring additional circuits or sensors. Four key control parameters, namely, phase shift ratio, duty cycle ratios, and switching frequency, are controlled for the converter to maintain ZVS turn-<sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small>, PFC, output voltage regulation, and reduced resonant inductor current ripple. The article outlines a detailed DMRSCR model to deduce the dependency of the four control and converter design parameters on the converter operation. Based on the model, a complete converter design process is provided. A DMRSCR prototype rated at 1.1 kW was built using the underscored design methodology to validate the proposed modulation scheme, reaching a peak efficiency of 98.27%.