Analysis of the admittance of symmetrical triple-layer flexural piezoelectric vibrator

Piezoelectric materials are frequently used as transducers. Piezoelectric bending mode elements can be used to harvest vibration energy because they can convert mechanical energy into electrical energy. In this article, we present the derivation of the equation for electrical admittance of the symmetrical triple-layer flexural piezoelectric vibrator. The triple-layer piezoelectric vibrator is here made into a sandwich: two layers of piezoelectric ceramics are separated by a thin layer of a conductive material. These two piezoelectric layers are often connected electrically in series when sensing or harvesting energy. The resonance mode equation of admittance for symmetrical triple-layer flexural piezoelectric vibrator is given. The equation can be used to analyze admittance characteristics and equivalent circuits and to calculate piezoelectric constants of symmetrical triple-layer flexural piezoelectric vibrators.