轴向预压缩双晶片动力学模型与特性分析

基于欧拉梁的假设，将双晶片简化为3层压电层合梁，由Hamilton原理建立系统的动力学模型，得到描述轴向预压缩压电双晶片的偏微分方程及特定边界条件，通过求解上述微分方程的边值问题得到双晶片在不同轴向力下的输出特性的解析表达式。利用有限元软件对双晶片进行仿真，验证了理论分析的正确性，增加理论分析结果的可信度。最后通过实验的方法研究双晶片的静、动力学特性，证明了施加轴向力可以降低双晶片的弯曲刚度和固有频率，显著增加其机电耦合效率，提高力和位移输出能力。轴向力虽然会影响双晶片启动时的位移峰值，但是对响应时间和带宽影响较小，大轴向力下双晶片仍具有带宽高与响应快的优势。

Dynamic Model and Characteristic Analysis of Pre-compressed Piezoelectric Bimorph

The dynamic model of the system is established based on the Hamilton principle where the bimorph is simplified into a 3-layer piezoelectric laminated beam according to the hypothesis of Euler beams. The analytical expressions of the output characteristics of the bimorph under different axial forces is derived from the solution of the partial differential equation and specific boundary conditions of the axial precompressed piezoelectric bimorph At the same time, the simulation is conducted to verify the correctness and gain the credibility of theoretical analysis. At last, the static and dynamic properties of bimorphs are studied experimentally. It is proved that the bending stiffness and natural frequency of the bimorph are reduced by the application of axial force. The electromechanical coupling efficiency is significantly increased and the output capability is improved. While the axial force affects the peak displacement of the bimorph at start-up, it has little effect on the response time and bandwidth. The bimorphs still have advantages over high bandwidth and fast response under large axial force.