Use of quasi-resonance principles with linearization process, in medium-power, high frequency converters-conception rules of corresponding synthetic thyristors

Two medium-power high-performance power converters for industrial applications that use bipolar transistors and insulated-gate bipolar transistors are described. The first is an isolated 3 kW DC-DC 500 V (380 V rectified and filtered) power supply whose frequency is variable up to 100 kHz. Efficiency is shown to be 94%, and the power-frequency product is 3*10/sup 8/ WHz. The principles developed (switch bidirectionality) allow this converter to work as a quasi-perfect voltage power supply. The second application is a one-phase DC-AC power converter whose power supply is 500 V (380 V mains rectified and filtered). This converter continuously provides 20 kW at a constant frequency of 20 kHz. Its power-frequency product is 4*10/sup 8/ WHz. This converter exhibits a pulse-width modulated mode with a fully controlled resonant switch. Quasi-resonance principles, corresponding switch structures using thyristor functions and the control of the devices which constitute synthetic thyristors are reviewed.<>