Design algorithm of a uniform magnetic field transmitter intended for the wireless charging of electric vehicles

This paper proposes to use uniform magnetic fields for wireless electric vehicle charging in order to resolve the problem of positioning the receiver (on the vehicle) over the transmitter (on the parking spot). A novel funnel-shaped coil structure is introduced to generate uniform magnetic fields, together with a design algorithm for determining the geometric parameters of the coil structure. This algorithm can be applied to the design of uniform magnetic fields of any size. Results show that magnetic fields produced by our design have fairly good uniformity; more than 71% of the coil area has a uniform field with a maximum percentage difference of the vertical component of the magnetic below 10%. The uniformity of the example is validated with finite element analysis (FEA).