Optimized Shielding Combination of The Ferrite Bars and Annular Aluminum Ring for WPT Systems

This paper introduces an enhanced shielding amalgamation comprising ferrite bars and an annular aluminum ring, particularly tailored for Wireless Power Transmission (WPT) systems. The electrical parameters of the system in the presence of ferromagnetic materials are obtained by the finite element method (FEM) simulation and experiments. And the annular aluminum plate’s effective shielding mechanism against the magnetic field is revealed. This is primarily attributable to the 'eddy current cancellation' principle, a consequence of the inverted magnetic field generated by numerous eddy currents. The contrastive results of simulation and experiments between a non-shielded scenario and a scenario employing collaborative shielding, utilizing both ferrite and an aluminum plate, manifests a substantial enhancement in transmission efficiency from 66.1% to 98.0%. Notably, despite this adjustment, the coupling between the receiver (RX) and transmitter (TX) retains considerable strength. The findings underscore the merit of incorporating a shielding strategy within WPT systems, offering insights into improving overall system performance.