A new design of an air core transformer for Electric Vehicle On-Board Charger

This paper compares two geometries of air core transformer, relevant for high frequency converters and high power densities: One logical toroidal, one innovative cylindrical. The manufacturing, the coupling parameter, the volume, and the flux leakage are examined in these topologies. The efficiency symbolizes a crucial parameter on power electronics, and a trade-off must ever be optimized between size and power. The proposed innovative structure permits to strongly increase the converter power density for an identical efficiency.