An Improved Magnetic Coupling Resonant Wireless Power Transfer System Based on Ferrite‐Nanocrystalline Hybrid Shielding Method

ABSTRACT Low‐power magnetic coupling resonant wireless power transfer (MCRWPT) systems are less efficient at long transmission distances due to magnetic leakage and losses. For this reason, combining ferrite‐nanocrystalline hybrid shielding and a relay coil, an improved MCRWPT system based on the LCC‐LCC compensation network is designed in this paper. Firstly, the transmission performance of the MCRWPT systems with S‐S and LCC‐LCC compensation networks are compared and analyzed. Secondly, the transfer efficiencies of the MCRWPT system are analyzed when the relay coil is added at different locations, and the transfer efficiencies of the system with single material shielding are compared. Finally, the transmission performance of the MCRWPT system with ferrite‐nanocrystalline hybrid shieling is analyzed using simulation and experiment. Experimental results show that the transfer efficiency of the low‐power MCRWPT system using relay coil and hybrid shielding increases from 40.38% to 69.17% when the input voltage is 40 V and the transmission distance is 250 mm. Compared with the MCRWPT system based on ferrite full shielding, the weight of the MCRWPT system has been reduced by 63.11%. The hybrid shielding method not only improves the transfer efficiency of the MCRWPT system and reduces its spatial magnetic leakage but also has certain cost advantages.