A Modified Three-Level Soft-Switching DC-DC Full-Bridge Converter

Abstract

This paper aims to present a modified three-level full-bridge dc-dc converter that can operate under soft-switching conditions for all switches in the circuit. There are 2 branches of three-level half-bridge inverter. The auxiliary inductances are used in the circuit in order to confirm the zero-voltage switching condition (ZVS) for all switches for wide load ranges. Moreover, the dc blocking capacitor is used for obtaining the zero-current switching condition (ZCS) for inner switches in the circuit. The proposed circuit was designed, analyzed and simulated at 2.56 kW of output power, 540 V of input voltage, 510 V of output voltage at 60° of phase shift angle and 50 kHz of switching frequency to confirm the possibility of the proposed theory.