Analysis, Design, and Implementation of a Bidirectional Double-Boost DC–DC Converter

Abstract

This paper presents a new bidirectional dc-dc converter with a high conversion ratio for renewable energy systems. The coupled-inductor technique is used to achieve a high conversion ratio with very simple control circuits. In discharging mode, the converter acts as a two-stage boost converter, controlling one power switch to achieve high-voltage step-up conversion. In charging mode, the converter acts as two cascaded buck converters that control two power switches simultaneously to achieve high-voltage step-down conversion. The operating principles and analysis of the steady-state characteristics are discussed in great detail. Finally, a 24-V/200-V prototype circuit with output power of 200 W is implemented to verify the feasibility of the proposed converter. The maximum efficiency levels in discharging and charging modes are about 94.3% and 91.6%, respectively.