Design and Performance Analysis of Single Sided Magnetic Coupler for Leakage Magnetic Field Reduction in a Wireless Power Transfer System with Ferrite and Alnico material

Wireless Power Transfer (WPT) systems have gained popularity due to their safety and convenience in various applications. WPT enables energy transfer through magnetic fields, eliminating the need for direct electrical connections between the transmitter (TX) and receiver (RX) sides. In this study, we designed and analyzed four types of coils with different couplers using ANSYS Maxwell simulation to investigate their performance in WPT systems. The four coil designs included Type I - a circular copper coil without a coupler. Type II -a copper coil with a conventional ferrite coupler; Type III -a copper coil with an optimized ferrite coupler; and Type IV - a copper coil with an optimized ferrite and alnico coupler. Simulation results revealed that Type II, with the conventional ferrite coupler, significantly improved the coupling coefficient (k) and mutual inductance (M) compared to the coil-only design (Type I). However, this improvement also increased magnetic field density (B), raising concerns about human safety and potential electromagnetic interference (EMI) issues. To address these concerns, we proposed an optimized ferrite coupler (Type III), which maintained high coupling efficiency and mutual inductance while limiting the magnetic field density to the same level as the conventional ferrite coupler. Furthermore, we explored a hybrid coupler design (Type IV) combining an optimized ferrite and an alnico coupler, resulting in higher magnetic field density and being suitable for applications requiring more vital magnetic fields. The study emphasizes the importance of carefully optimizing coupler designs to achieve efficient power transfer while considering safety and EMI implications. These findings provide valuable insights for designing WPT systems tailored to specific application needs. In conclusion, this research contributes to the advancement of WPT technology and provides a valuable guide for optimizing coupler designs to maximize power transfer efficiency and magnetic field characteristics in WPT systems..