悬臂梁式压电振动能量收集器的疲劳分析

建立了悬臂梁式压电振动能量收集器的有限元模型,通过模态分析求解了其一阶固有频率,并通过实验验证了求解结果的准确性。对所建立的有限元模型进行静态分析后将静态分析的结果导入ANSYS nCode DesignLife中进行疲劳分析,结果表明,随着激励位移幅值的增大,压电层的应变与其成线性关系增大,而疲劳寿命迅速缩短,当激励位移增大1倍时,疲劳寿命缩短了284倍。因此在实际应用中,要综合考虑压电悬臂梁的输出电压及压电陶瓷层的疲劳寿命,才能实现最大的电能输出。

Fatigue Analysis for Cantilever Piezoelectric Vibration Energy Harvester

The finite element model of cantilever piezoelectric vibration energy harvester is established. Its first order natural frequency is solved by modal analysis and an experiment verifies the accuracy of the result. The static analysis of the established finite element model is carried out, then the results is conducted into ANSYS nCode DesignLife for fatigue analysis. The results show that with the increase of excitation displacement amplitude, the strain of piezoelectric layer increases linearly but the fatigue life shortens rapidly. When the excitation displacement doubles, the fatigue life is reduced as much as 284 times. Therefore, the output voltage of piezoelectric cantilever beam and the fatigue life of piezoelectric layer should be considered comprehensively in order to achieve maximum power output.