Genetic Algorithm Based Optimization of Circular Planar Coil Geometry With Homogeneous Magnetic Field Distribution

A prominent problem in planar resonant wire-less power transfer (WPT) systems is instability of efficiency and load power due to position misalignment of the receiver (RX) coil relative to postion of the transmitter (TX) coil. In order to keep stable efficiency and load power even in such misaligned condition it is necessary to design transmitter coil which generates homogeneous magnetic field in charging plane. In this paper, a geometry of planar transmitter coil which consist of multiple concentric circles is optimized by utilizing genetic algorithm. optimization goal is achieving as large as possible homogeneous region, i.e. portion of charging plane which is characterized by homogeneous magnetic field. Magnetic field evaluations are done by FEMM software. Proposed coil achieves continuous homogeneous region at 44.4% surface of charging plane. optimized coil and its homogenous region is compared to the state-of-the-art.