Modeling and Characteristic Analysis of Wireless Ultrasonic Vibration Energy Transmission Channels through Planar and Curved Metal Barriers

Abstract

Wireless ultrasonic vibration energy transmission systems through metal barriers based on piezoelectric transducers have drawn a lot of focus due to the advantage of nonpenetration of the barriers, thus maintaining the integrity of sealed structures. It is meaningful to investigate appropriate modeling methods and to characterize such wireless ultrasonic energy transmission channels with different geometric shapes. In this paper, equivalent circuit modeling and finite element modeling methods are applied to the planar metal barrier channel, and a 3-dimensional finite element modeling method is applied to the cylindrical metallic barrier channel. Meanwhile, the experimental setup is established and measurements are carried out to validate the effectiveness of the corresponding modeling methods. The results show that Leach's equivalent circuit modeling method and finite element modeling method are nearly similarly effective in characterizing the planar metal barrier channel. But for a cylindrical metal barrier, only the three-dimensional finite element modeling method is effective. Furthermore, we found that, for the planar barrier, the effect of standing waves on the efficiency of wireless energy transmission is dominated. But for the curved barrier, only the resonant phenomenon of the piezoelectric transducer exists.

The Modeling Framework for Through‐Metal‐Wall Ultrasonic Power Transmission Channels Based on Piezoelectric Transducers

“…The material of the pipe and the transition piece is stainless steel. The inner diameter of the metal pipe is 75mm, the external diameter is 85 mm, and length is 200mm [23].…”

“…Two mechanical ports denoted by B and F represent the back and front of a piezoelectric transducer, and a single electrical port E is assigned to the assumption that the opposite side of the piezoelectric transducer is grounded. The internal electric symbols in the model denoted by F 1 , F 2 represent two voltagecontrolled voltage sources and E 1 is a current-controlled current source [23].…”

“…Leach's equivalent circuit model of the ultrasonic wireless power transmission channel through a planar metal wall for SPICE simulation[23].…”

“…dimensional geometric model of the ultrasonic power transmission channel through a cylindrical metal pipe[23]. Input impedance characteristics of the channel through a cylindrical metal pipe[23].…”

Analytical optimization of piezoelectric acoustic power transfer systems

“…Yang et al [5] have developed a highly-efficient AC/DC converter for APT, delivering up to 15.7 W at 5 V-DC. Other teams studied structures different than flat metallic walls, such as pipes, and transmitted power through their thickness [6], or along their length with up to 4 mW transmitted over a distance of 1 m, but with a very low efficiency of 0.1% [7,8]. Others studied the acoustic power transmission through multi-layers channel including 88.3 mm of water [9].…”