压电悬臂梁俘能器输出特性仿真分析

Simulation Analysis of Output Characteristics of Piezoelectric Cantilever Beams Harvester

为了研究压电俘能器的振动频率、内阻抗、负载及输出功率之间的耦合关系,基于ANSYS APDL软件,对单、双晶串联、双晶并联等多种不同配置方式的压电悬臂梁俘能器进行了压电-电路耦合分析。研究表明,俘能器内阻抗随振动频率呈现非线性变化,在短路谐振频率处达到最小值,在开路谐振处达到最大值;俘能器内、外阻抗匹配时,俘能器输出功率达到最优值;俘能器阻尼较小时,最优输出功率出现在短路谐振与开路谐振处,随着阻尼比逐渐增加,最优输出功率出现在两者之间,且只有一个峰值。

In order to study the coupling relationship among the vibration frequency, the internal impedance, the load and the output power of the piezoelectric energy harvester, the piezoelectric circuit coupling analysis of the piezoelectric energy harvesters with different configurations of single crystal series, double crystal series, double crystal parallel is carried out based on ANSYS APDL software. The results show that the impedance of the energy harvester exhibits a non linear change with the vibration frequency, which reaches the minimum value at short circuit resonant frequency and reaches the maximum value at open circuit resonance. The output power of the energy harvester reaches the optimal value when the internal and external impedances match. When the damping ratio of the energy harvester is relatively small, the optimal output power appears at short circuit resonant and open circuit resonance. As the damping ratio gradually increases, the optimal output power occurs between short circuit resonant and open circuit resonance, and there is only one peak.