Non-isolated high step-up converter based on boost integrated half-bridge converter

Abstract

A classical boost converter has a limited voltage step-up ratio because of its parasitic resistances, which does not make it suitable for high step-up applications. Therefore, to obtain a high step-up capability with high efficiency, non-isolated high step-up technique based on isolated type converters is introduced in this paper. By stacking the secondary sides in addition to the primary side, high step-up conversion ratio can be achieved. Moreover, a careful choice isolated converter provides zero-voltage-switching (ZVS), low voltage stress on devices, and continuous input current. The operational principle and characteristics of proposed converter are presented, and verified experimentally with a 140-W, 24-Vdc input, 150~250-Vdc output prototype converter for a LED driver.