Design and Properties of Piezoelectric Vibrator with Generating Function by FEM Analysis

Bimorph type piezoelectric vibrator with generating function is designed using Finite Element Method (FEM) and fabricated. Design of piezoelectric vibrator by FEM is focused at its length and the weight of added mass. Also, the vibration and charging properties of the fabricated piezoelectric vibrator are investigated. As the FEM analysis results, when the piezoelectric vibrator is the length of 18 mm and the additive weight of 0.3 g, its resonance frequency decrease to 150 Hz. Also, when input voltage of 20 V is applied, output voltage is 10.285 V in generating element. As the properties of piezoelectric vibrator fabricated, when input voltage is 20 Vrms, the acceleration of piezoelectric vibrator and output voltage are about 1.1 G and 10.18 Vrms, respectively. When gold capacitor of 0.0066 [F] is used as the load, the output voltage is about 3 [VDC] after 3600 [sec] driving time.