Modeling and Optimization of a Through-Metal Acoustic Wireless Power Transfer System

This paper presents the design of a through-metal acoustic wireless power transfer (AWPT) system using piezoelectric transducers (PT) as transmitter (TX) and receiver (RX). An equivalent circuit model using measured impedance parameters is used to model the complete PT-to-PT electromechanical conversion. The system is designed by sweeping frequency, load resistance, and compensation design to maximize transferred power. Boundary constraints are presented based on temperature and voltage limits the PTs can withstand. An optimal design staying within the operating bounds is then chosen and tested in hardware. The designed system is fabricated and verified experimentally for varying voltage levels. The prototype system has been tested up to 160 V dc input and 41 W output.