Modelling and Design for Position-Free Inductive Couplers with the Homogeneous-Flux Transmitting Coil in Wireless Power Transfer Systems

This paper presents a design algorithm to combine the analytical magnetic flux modelling and the genetic algorithm (GA) for position-free inductive couplers in inductive power transfer (IPT) systems. The design concept can enhance the position tolerance significantly by making the transmitting coil generate a homogeneous flux density at the target receiving position. Based on the analytical magnetic flux models and the proposed design algorithm, the winding configurations for the air-core transmitting coils or magnetic shielded transmitter coils can be directly generated. Two case studies demonstrate the design algorithm: the analytical magnetic flux models and the generated homogeneous flux density are verified by 2D FEM simulation and measurement results. Furthermore, the non-interference for the inverters’/rectifiers’ operation with the position shift is experimentally verified on the 6.78 MHz prototypes.