Bidirectional contactless power transfer system expandable from unidirectional system

Contactless power transfer (CPT) systems with primary series and secondary parallel capacitors (SP topology) are useful for charging electric vehicles. However, SP topology is not suitable for bidirectional power transfer. This paper introduces a novel SPL topology for bidirectional CPT systems that is realized by adding an inductor and an inverter to the SP topology. The 3 kW and 160 mm gap bidirectional test results show that the efficiency of G2V is 92.5%, and the efficiency of V2G is 93.4%, which are approximately equal to the efficiency of the unidirectional SP topology system of 93.1%.