Design of resonant circuit for zero-current-transition techniques in 100-kW PEBB applications

In high-power inverters and power-factor-correction rectifiers hard-switching techniques produce high switching losses, high power dissipation in capacitors, and severe conductive electromagnetic interference. Soft-switching techniques may reduce these problems; in particular, zero-current-transition (ZCT) techniques are attractive in high-power converters, where the minority-carrier devices, such as insulated gate bipolar transistors, are the power switches. The aim of this paper is to show theoretical expressions for designing of auxiliary circuit and variable timing control scheme in applications where ZCT techniques are used. In order to prove the theoretical approach, extensive analysis is first achieved on the basis of simulation results and then validated on the basis of experimental tests.