Analysis and design of voltage-mode resonant Cuk converter

Two-types of a voltage-mode resonant Cuk converter, half-wave and full-wave types, with a coupled inductor are analyzed by introducing the effects of parasitic inductances. The characteristics of the coupled inductor used in these resonant converters are investigated. It is found that the voltage waveforms of the coupled inductor operating at high frequency differs from that of the conventional pulsewidth-modulated Cuk converter, and that it affects the input and output current ripple characteristics. This is due to some parasitic inductances existing in the resonant circuit loop and the diode reverse recovery. A method is proposed to satisfy the coupling condition of the coupled inductor by suppressing these effects. The validity of the analysis is confirmed by comparisons with experimental results