Fixed-Frequency Current-Fed LCL Series Resonant Soft-Switching Converter With Capacitive Doubler

Abstract

Electrification of power take-off (ePTO) system is an effective way to minimize the fossil fuel consumption from heavy duty electric vehicles, where a high gain dc/dc converter is needed to integrate PV/fuel-cell. Popular high-gain dc/dc converters such as PWM type, clamped and unclamped quasi-resonant converters cant serve such applications as they fail to achieve high-efficiency, wide load and input voltage range for soft-switching, constant switching frequency and high transformer utilization (TUF) simultaneously. In this paper, a LCL series resonance based high-gain load resonant dc/dc converter is proposed to eliminate the above-mentioned drawbacks. A series resonant tank in the converter is able to adapt tank current in proportion to load demand leading to minimum losses and high TUF. Further, energy is stored in the series and parallel resonant inductors, in proportion to load demand and constant load voltage respectively, ensures soft-switching of the converter through full load to light load conditions. On the other hand, proposed converter operates with constant switching frequency to adopt simple PWM modulation to regulate load voltage against input and load disturbances. This paper presents operation, analysis, modeling and design of the proposed converter. Hardware setup has been mounted and tested to verify he proposed theory.