Comparison About Design Methods of Tonpilz Type Transducer

Abstract

A Tonpilz type piezoelectric ceramic ultrasonic transducer is investigated through the methods of equivalent circuit and finite element analysis(FEA). The emphasis of this paper lies in the difference between the two methods. Essentially, the piezoelectric constitutive equation is the common law of them. Derived from this equation, the Mason’s equivalent circuit and the frequency equation of the piezoelectric transducer is obtained, and then the finite element control equation is obtained. A mason’s equivalent circuit model and a 1/4 symmetry finite element model of the Tonpilz type piezoelectric ceramic ultrasonic transducer are both constructed. A comparison about the frequency performance and the admittance performance which are respectively obtained from the two methods and the corresponding test shows that, the method of FEA is more quickly and accurately, and its analysis error is controlled within 5%. What is worth to mention is that some performance and the vibration of the transducer have been predicted distinctly through FEA. So FEA is suitable to the piezoelectric transducer. A transducer prototype which is made according to the analysis result has a good performance and satisfying applied requirements.