Design of coils on printed circuit board for inductive power transfer system

Abstract

Due to the different application prospects, the coils of inductive power transfer (IPT) systemvaries. The coils on printed circuit boards (PCB) have drawn considerableattention gradually. However, the applications mainly involve portable equipmentand implantable medical devices operating at a high frequency, not fit for IPTsystem. In this paper, an IPT system based on PCB coils were designed. All thecharacteristics of single turn coils on a single‐layer, multi turns coils on asingle‐layer and multi turns coils on multi‐layers of printed spiral coils(PSCs) were analysed and calculated. The self‐inductance and mutual inductanceof the series windings on PSCs were modeled and calculated firstly. Anequivalent circuit of coils were proposed to simplify the calculation andfacilitate the analysis. Furthermore, in order to increase mutual inductance andtransfer more power, the multi‐layer coils connecting in series were designedfor the first time and the inductance parameters can be acquired by the means ofproposed method. The analyses on coils model were verified by simulations usingfinite element method and measuring. Finally, the coil characteristics on IPTsystem were verified by the circuit simulation and experiment results and thedesigned coils can meet the desired requirements.