Step-Up DC-DC Switching Converter With Single Switch and Multi-Outputs Based on Luo Topology

Abstract

In this paper, a step-up DC-DC multi-output converter is introduced by integrating a super-lift Luo converter, flyback topology, and coupled inductor concept. The proposed multi-output converter has positive output super-lift structure while simultaneously generating step-up voltages in its outputs. The proposed step-up converter has two non-isolated and one isolated output with a simple structure using one switch and one magnetic core. There is no voltage spike by the leakage inductance of the coupled inductor across the switch in the proposed converter. Therefore, the switch has low-stress voltage. The energy in the leakage inductor is recycled leading to higher efficiency in comparison to similar converters with the coupled inductor. The operating principles and the characteristics of the proposed converter are analyzed and discussed. The experimental results of 110W prototype verify the theoretical analysis and the benefits of the proposed converter in comparison to similar multi-output converters. The conducted electromagnetic interference evaluation of the proposed converter is presented and it is reduced using a common-mode choke.

Keywords

• Conducted EMI
• coupled inductor
• Luo converter
• multi-outputs
• step-up DC-DC conversion