Operating characteristics in LCLC resonant converter with a low coupling transformer

Conventionally, to transfer the power from the primary power to the secondary one, high frequency series resonant converter has been widely used for the contact-less power supply system. However, the high frequency senes resonant converter has the disadvantages such as the low efficiency, the high voltage gain characteristics and deviation of the phase angle in the overall load range. To improve these disadvantages, in this paper, the characteristics of the high efficiency and unit voltage gain as well as in-phase between input and current waveforin are obtained with the proposed three-level LCLC (Inductor-Capacitor- Inductor-Capacitor) resonant converter. The proposed system results are verified by the simulation based on the theoretical analysis and the 4kW experimental prototype.