Study of Characteristics of Multi-Layer Piezoelectric Transformers by using 3-D Finite Element Method

Piezoelectric transformers are electronic devices made from piezoelectric materials. The piezoelectric transformers as the name implied are used for changing voltage signals from one level to another. Electrical energy carried with signals is transferred by means of mechanical vibration. Characterizing in both electrical and mechanical properties leads to extensively use and efficiency enhancement of piezoelectric transformers in various applications. In this paper, study and analysis of electrical and mechanical properties of multi-layer piezoelectric transformers in forms of potential and displacement distribution throughout the volume, respectively. This paper proposes a set of quasi-static mathematical model of electromechanical coupling for piezoelectric transformer by using a set of partial differential equations. Computer-based simulation utilizing the three-dimensional finite element method (3-D FEM) is exploited as a tool for visualizing potentials and displacements distribution within the multi-layer piezoelectric transformer. This simulation was conducted by varying a number of layers. In this paper 3, 5 and 7 of the circular ring type were used. The computer simulation based on the use of the FEM has been developed in MATLAB programming environment.

Authors:

• C. Panya-Isara
• T. Kulworawanichpong
• P. Pao-La-Or

Keywords:

• Multi-layer Piezoelectric Transformer
• 3-D Finite Element Method (3-D FEM)
• Electro-mechanical Coupling
• Mechanical Vibration

References:

[1] N.A. Demerdash and D.H. Gillott, "A new approach for determination of eddy current and flux penetration in nonlinear ferromagnetic materials," IEEE Transactions on Magnetics, Vol.74, pp. 682-685, 1974. K.F. Kwok, P. Dong, K.W.E. Cheng, K.W. Kwok, Y.L. Ho, X.X. Wang and
H. Chan, "General Study on Piezoelectric Transformer," IEEE Transactions on Ultrasonics, Vol. 55, pp.216-220, 2002.
[2] R. Lerch, "Simulation of Piezoelectric Devices by Two and Three Dimension Finite Element," IEEE Transactions on Ultrasonics, Vol. 37,
No. 2, pp.233-247, 1990.
[3] J.S. Wang and D.F. Ostergaard, "A Finite Element-Electric Circuit
Coupled Simulation Method for Piezoelectric Transducer," IEEE Transactions on Ultrasonics, Vol. 59, pp.1105-1108, 1999.
[4] C. Christopoulos, The Transmission-Line Modeling Method: TLM, IEEE
Press, USA, 1995.
[5] P. Pao-la-or, T. Kulworawanichpong, S. Sujitjorn and S. Peaiyoung,
"Distributions of Flux and Electromagnetic Force in Induction Motors:
A Finite Element Approach," WSEAS Transactions on Systems, Vol. 5,
No. 3, pp.617-624, 2006.
[6] P. Pao-la-or, A. Isaramongkolrak and T. Kulworawanichpong, "Finite
Element Analysis of Magnetic Field Distribution for 500-kV Power Transmission Systems," Engineering Letters, Vol. 18, No. 1, pp.1-9,
2010.
[7] R.W. Lewis, P. Nithiarasu and K.N. Seetharamu, Fundamentals of the
Finite Element Method for Heat and Fluid Flow, John Wiley & Sons, USA, 2004.
[8] M.A. Bhatti, Advanced Topics in Finite Element Analysis of Structures,
John Wiley & Sons, USA, 2006.
[9] P.I. Kattan, MATLAB Guide to Finite Elements (2nd edition), Springer
Berlin Heidelberg, USA, 2007.