Medium Voltage High Power High Frequency DC Power Supply for Charging Application

Abstract

High power high frequency isolated DC-DC converter with higher efficiency is main area of research in power electronics. Now a days the most popular and useful topology employed for high power isolated DC-DC converter is T-type multilevel converter, with the following advantages:(a) transformer isolation give symmetrical operation (b) PWM with constant frequency, (c) zero voltage switching, and (d) multilevel voltage applied to the primary winding of the transformer. The proposed T-type topology is composed of four switches in one leg. This topology enables a high frequency operation with reduced switching losses by applying different types of switching patterns it can balance the current in a dc link capacitor. Proposed topology is designed for 150 kW DC power supply at 18 kHz Frequency and it is simulated in PSIM environment. Prototype model is implemented and tested with 33.6 kW DC power supply at 18 kHz frequency by use of SI-IGBT switches with high efficiency.