Study on the method of enhancing power density in wireless energy transmission

In wireless power transfer (WPT) systems, the design of coupling coils plays a crucial role in power transfer. To increase the coupling coefficient, ferrite is added to conventional couplers. However, this can drastically reduce the power density of the system. In this paper, without changing the area of the transmitting coil, increase the power density of the system by increasing the number of the transmitting coil turns, combined with the application of ultra-thin magnetic material on the surface of the coupling coil. Based on the circuit principle, Model the equivalent circuit model of the system Analyze the influencing factors of the output power of the system. Then the 3D model was built by Ansys Maxwell to simulate the performance metrics under various scenarios, especially the coupling coefficient k and mutual inductance. Finally, it was verified through experiments that the combination of appropriately increasing the number of coil turns and adding ultra-thin magnetic materials will significantly increase the self-inductance, mutual inductance and coupling coefficient of the coupling coil, and improve the power density of the system.