Comparative Analysis of Ferrite Blocks and Magnetic Concrete in Wireless Power Transfer Systems

In high-power wireless power transfer (WPT) systems, ferrite blocks (FBs) and magnetic concrete (MC) are commonly used materials for fabricating magnetic components, both demonstrating notable performance. However, few comparative studies have examined their respective effects on WPT systems, leaving their differences and advantages insufficiently explored. This paper presents a comparative analysis of FBs and MC in WPT systems, focusing on their impacts on the coupling coefficient and system efficiency. First, the magnetic circuit characteristics of WPT system couplers are analyzed to identify the critical factors affecting the coupling coefficient. Then, magnetic components made of FBs and MC are designed and optimized using finite element analysis (FEA) to maximum the coupling coefficient under constrained conditions. These components are subsequently fabricated and integrated into a WPT prototype, with performance validated through experiments. Simulation and experimental results show that both FB and MC couplers significantly improve the coupling coefficient compared to coil-only coupler without magnetic components. However, the FB coupler achieves greater improvement. Efficiency tests at an output power of 2 kW further confirm that the prototype using the FB coupler demonstrates higher efficiency than the one using the MC coupler.