Capacitive wireless power transfer system with a 3D-functional coupler for maintenance-free industrial robots

This paper presents a capacitive wireless power transfer system that employs a three-dimensional (3D)-functional coupler for obtaining maintenance-free industrial robots. To enhance the vital coupling coefficient of the coupler within a confined space, such as a rotary joint, we fabricated a 3D capacitive coupler. Additionally, by employing polytetrafluoroethylene (PTFE) resin with a high Q factor for electrode fixation, a theoretical maximum efficiency of 99.3% was achieved. Finally, we designed a system that successfully produced a transmission of 5.76 W with a total DC-DC efficiency of 73.0% at 13.56 MHz and an arm chuck operations utilizing both power and pneumatic pressure.