Analysis of transformer leakage inductance and overlap effects in the series-parallel resonant converter

Fundamental frequency techniques are used to derive a set of equations for the series parallel resonant converter, including transformer leakage inductance, overlap effects and distortion of the parallel capacitor voltage. A more accurate approximation of the converter operation is provided than in previous analyses, and this also allows leakage inductance effects to be examined. The voltage conversion ratio for the converter is shown for several different operating points and leakage inductances. The results are discussed and verified with simulation results, and also experimentally with a 1 kW, 100 kHz prototype converter.