Compact contactless power transfer system for electric vehicles

Electric vehicles (EVs) have been attracting considerable interest recently. A contactless power transfer system is required for EVs. Transformers can have single-sided or double-sided windings. Transformers with double-sided windings are expected to be more compact and lightweight than transformers with single-sided windings. A contactless power transfer system for EVs needs to have a high efficiency, a large air gap, good tolerance to misalignment and be compact and lightweight. In this paper, a novel transformer using series and parallel capacitors with rectangular cores and double-sided windings that satisfies these criteria has been developed, and its characteristics are described. It has an output power of 1.5 kW and an efficiency of 95% in the normal position. To reduce the cost of expensive ferrite cores, a transformer with split cores is also proposed.