悬臂梁单晶压电发电振子电压输出特性的有限元仿真分析

Finite Element Simulation Analysis of Voltage Output Characteristic of Single Crystal Piezoelectric Vibrator in Cantilever Beam

为了解决化学电池为低功耗电子产品供电中存在的问题,对悬臂梁单晶压电发电振子的电压输出特性进行了分析。根据欧拉伯努利方程和压电学理论,建立了悬臂梁式压电发电振子的电压输出特性数学模型,并对压电振子长度、金属基板与压电晶体的长度比,以及金属基板材料对悬臂梁压电发电振子的电压输出特性进行了有限元仿真分析。结果表明:所建立的数学模型与仿真分析结果基本一致;晶体板与金属基板的长度比存在一个最佳值,使得压电振子的输出电压达到最大,且随着金属基板弹性模量的减小,压电振子的输出电压逐渐减小;当金属基板分别为不锈钢、硅、磷青铜和铝合金时,晶体板与各金属基板的最佳长度比分别为0. 60,0. 65,0. 70,0. 75。

In order to solve the problem that the chemical battery supplies power for low power electronic products, the voltage output characteristics of the cantilever single crystal piezoelectric vibrator is analyzed. According to the Euler Bernoulli equations and piezoelectric theory, a mathematical model of the voltage output characteristic of a cantilever beam type piezoelectric vibrator is established. The finite element simulation of the piezoelectric oscillator length, the length ratio of metal substrate to piezoelectric crystal and the voltage output characteristics of metal sub-strate piezoelectric cantilever generator are carried out. The analysis results show that the mathe-matical model established is in agreement with the result of simulation analysis. The optimum value of the length of the crystal plate and the metal substrate enables the output voltage of the piezoelectric vibrator to reach the maximum. With the decrease of the elastic modulus of the metal substrate, the output voltage of the piezoelectric vibrator is gradually reduced. When metal substrates are stainless steel, silicon, phosphor bronze, and aluminum alloy, the optimum length ratio of crystal plate to metal substrate is 0. 60,0.65,0.70,and 0. 75 respectively.