An Isolated Boost-Three Level Bi-directional DC-DC Converter with Phase Shift PWM

Abstract

A novel bi-directional DC-DC converter applicable to micro-grid is proposed in this paper, which combines traditional boosttype converter and three-level converter. Excellent power transmission ability (including voltage step-up and step down) can be obtained by deploying phase-shift control strategy. The proposed converter with three-level topology is also capable to lower the voltage stress of the second stage switches to 50%. Operation modes have been analyzed in detailin the paper. A 3-kW laboratory prototype was designed and tested for performance evaluation. Experimental results indicate the effectiveness and stability of the system.