Soft-switching boost converter for medium power applications

A novel two-phase zero voltage switching boost 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, complex transformer. The possibility of using large resonant capacitors results in a considerable turn-off loss reduction. Dividing the power among the two identical 180° shifted phases of the converter contributes to reduced input and output current ripples and results in lower ratings for the switches and passive components. Steady state and dynamic analysis of the 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 IGBT´s are predominantly used as power switches. The results are verified on a 6 kW prototype.