Design of Wireless Power Transfer Cage for Uniform Magnetic Field to Implantable Medical Devices Mounted on Animals

Many studies are conducted to apply wireless power transfer (WPT) technology to ensure non-invasiveness and minimize maintenance of implantable medical devices (IMDs). Commercialization of medical devices involves animal testing. During animal testing, misalignment between the transmitter and receiver can occur due to the animal's free movement, which lead to a decrease in power transfer capacity and efficiency, or even to a disruption in power transfer. Therefore, this paper proposes a cage-type WPT coil design method to deliver uniform power to a receiver coil whose position changes. The proposed method divides one transmitter coil into several zones and creates a uniform magnetic field by varying the design for each zone. By adjusting the current direction, the magnetic field within the transmitter coil can be shaped, and the number of turns and the spacing between sections can be designed to improve the performance of the WPT system. It can be confirmed that the proposed method is capable of forming a uniform magnetic field and delivering uniform power through 3D EM simulation and circuit simulation.