Inverting Zero-Current-Switching Buck Converter

A zero current switching (ZCS) inverting buck converter is presented. Due to ZCS, the switching losses of the converter are minimized. The converter passes through four modes. The modes of operation are explained by mathematical description and with the help of the phasor u-Zi diagram. The dimensioning of the devices is explained. The control of the converter is easy, because the diodes turn off naturally. The energy transfer of the converter is analyzed. Simulation results and measurements are shown. This resonant converter is useful for a step-down gain between 0.2 up to 0,9 and reasonable for battery chargers and renewable energy applications. A concept to reduce parasitic ringing during the idling phases of the converter is also presented.