Development and evaluation of single sided flux couplers for contactless electric vehicle charging

Inductive Power Transfer (IPT) is a practical and preferable method for recharging stationary and moving Electric Vehicles (EV) because it is safe, convenient and reliable. The performance of the magnetic couplers that transfer power determines the overall feasibility of a complete system. Single sided flux couplers have a unidirectional flux pattern and can be used under an EV with minimal loss to the (steel) chassis. Circular pads are single sided and the most common topology and these are investigated with consideration of magnetic field leakage guidelines. Following this, a new polarized coupler topology (referred to as a “Double-D-Quadrature” (DDQ)) is presented. An interoperability study with conventional circular couplers shows this DDQ pad is completely compatible and offers a significantly larger charge zone.