Investigation of the Effect of Self-Heating on Through-Metal Ultrasonic Power Transmission Efficiency

Power transmission through sealed enclosures is of interest due to its various applications, such as powering sensors inside pressure vessels or charging medical implants. Electromagnetic waves cannot pass through sealed metallic enclosures, whereas ultrasonic power transfer is a valuable alternative for these systems. A typical ultrasonic power transmission (UPT) system consists of two piezoelectric transducers bonded on either side of a metallic barrier, where the transducers transmit and receive elastic waves and convert the mechanical energy into electrical energy. However, various sources of loss (including dielectric and mechanical losses) exist within piezoelectric transducers, which lead to self-generated heat that affects the efficiency of the UPT system. In this work, the effects of temperature on UPT efficiency are studied using both numerical and experimental methods.