Design and analysis of switched-coupled-inductor switched-capacitor step-up DC-DC converter

摘要

The study presents a high-gain closed-loop configuration of switched-coupled-inductor switched-capacitor (SCISC) converter via integrating with a pulse-width-modulation-based (PWM) controller for the goal of step-up DC-DC conversion/regulation. The SCISC power part consists of switched-coupled-inductor booster (SCI booster) and switched-capacitor tripler (SC tripler), and the step-up voltage gain is performed by using appropriate duty ratio D of PWM and turn ratio n of coupled inductor. Although increasing n or raising D makes a higher gain, it often results in the larger weight/volume or magnetic bias/saturation of coupled inductor. Here, the SC tripler can provide for an extra gain to ease these stresses of the coupled inductor. Further, this controller is engaged not merely in doing topological operation and timing, but in enhancing output regulation and/or output robustness (against source/loading variation). The related studies are demonstrated as follows: modelling, steady-state response, voltage conversion ratio value, power efficiency, capacitance/inductance selection, system stability and control design. At the end, the simulation results are obtained to check the design/analysis validity, and the experimental results are verified on the prototype of SCISC to display the effect of the proposed scheme.