Two-phase zero-voltage switching boost converter for medium power applications

A novel two-phase zero-voltage switching boost power converter is proposed. The proposed converter overcomes some limitations of the DC/DC resonant-type converter, such as high circulating energy, limited ZVS load range and complex transformer. The turn-on instant of the switches comes after zero-voltage detection of the voltage across them and there is no load limitation for soft switching. The possibility of using large resonant capacitors results in a considerable turn-off loss reduction. Dividing the power among the two identical 180/spl deg/ shifted phases of the converter contributes to reduced input and output current ripple and results in lower ratings for the switches and passive components. Steady state and dynamic analysis of the power converter are presented for design purposes. The new converter is attractive at medium-power DC/DC applications with output/input voltages ratio between 2 and about 6, where IGBTs are predominantly used as power switches. The principle of operation, features and design considerations of the proposed power converter are described and verified on a 6 kW, IGBT-based experimental circuit.