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Ultrasound acoustic energy transfer systems are receiving growing attention in the area of contactless energy transfer for its advantages over other approaches, such as inductive coupling method. To date, most research on this approach has been on modeling and proof-of-concept experiments in the linear regime where nonlinear effects associated with high excitation levels are not significant. We present an acoustic-electroelastic model of a piezoelectric receiver in water by considering its nonlinear constitutive relations. The theory is based on ideal spherical sound wave propagation in conjunction with the electroelastic distributed-parameter governing equations for the receiver’s vibration and the electrical circuit.
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Comparison of various models for piezoelectric receivers in wireless acoustic power transfer
Piezoelectric transduction has lately been employed in wireless acoustic power transfer (APT) for powering electronic components that cannot be accessed easily, such as deep-implanted medical devices. Typically, the axial (or thickness) vibration mode of piezoelectric materials is used to generate acoustic waves that propagate through a medium, which are then converted back into electricity and delivered to an electrical load at the receiver end. The piezoelectric receiver can have various aspect ratios (length/diameter) in a given APT application. This work aims to develop and compare various models, such as the classical theory, Rayleigh’s theory, and Bishop’s theory, as well as finite-element model simulations, for different aspect ratios with an emphasis on those with comparable dimensions. Following analytical modeling and numerical simulation efforts, both in air and fluid loaded impedance frequency response functions are compared to report the valid aspect ratio ranges of the respective theories and their limitations, along with comparisons against experiments.
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- Award ID(s):
- 1727951
- PAR ID:
- 10170627
- Date Published:
- Journal Name:
- Proceedings of SPIE Smart Structures/NDE Active and Passive Smart Structures and Integrated Systems XIII
- Volume:
- 10967
- Issue:
- 109670S
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2515377
