A new wireless EV charger using single switch ZVS resonant inverter with optimized power transfer and low-cost PFC

This paper deals with a cost effective IPT wireless EV battery charger which incorporates the simplest quasi-resonant soft switching pulse modulated inverter. In the first place, the operating principle of the single-ended high-frequency resonant inverter linked IPT DC-DC converter treated here is described. This two planar coupling coils type wireless resonant DC-DC converter can efficiently operate under a condition of ZVS transitions on the basis of the self-excited pulse processing scheme due to zero voltage detecting method of quasi-resonant capacitor voltage. In the second place, illustrated is a comparative study of wireless power transfer circuits. Power receiving circuit is optimized successfully from a viewpoint of transfer power. Furthermore a low-cost power-factor correction by active filtering is described herein. The waveform of the input current in pilot study of this wireless EV charger has very low harmonic distortion by the PFC control of the inverter and the design of the filter circuit parameters.