Flexible Inductive Wireless Power Transfer System with an Onboard Temperature Sensor

Inductive wireless power transfer has been recognized as a feasible solution to expand the lifespan of wearable and implants. Apparently, these devices have to be mechanically flexible. In this paper, we propose a novel flexible inductive wireless power transfer system with an onboard temperature sensor. We use the flexible Kapton (polyimide) film and printed silver traces to create the circuit layout of the system. The fully flexible and bendable wireless power transfer system occupies an area of 1 cm × 4 cm. Experimental results indicate that the system can deliver 3.3 V DC voltage to the load at the operational frequency of 3.5 MHz when the receiving unit is at a distance of 4 mm. Furthermore, we demonstrate the capability of the proposed system to power up the embedded temperature sensor in two mediums, i.e., air and water. It was observed that the temperature sensor has a linear response in both mediums, which clearly confirms the reliability and stability of the scavenged power by our proposed system.