压电双晶连接形式对振动发电机力电输出特性的影响

Effects of Piezoelectric Bimorph Connection on the Force-electrical Performances of Vibration Generator

为了分析压电双晶体连接形式对振动发电机力电输出特性的影响,并有效改善发电机综合性能,考虑发电机机械端的力-电耦合与电路端的电-电耦合作用,利用压电本构方程建立了双晶压电悬臂式振动发电机的有限元分析动力学方程,利用ANSYS软件建立了相应的有限元机电耦合分析模型,对比分析了在相同外力激振条件下,压电双晶不同连接形式对发电机输出力特性(末端振动速度)和电特性(电压、电流和电输出功率)的影响。最后,对两种类型发电机的电输出功率进行优化分析,得到了压电双晶不同连接形式时发电机的优化负载电阻和最大输出功率。研究结果表明:串联型振动发电机的优化负载电阻是并联型发电机优化负载电阻的4倍;串联型发电机具有较大的输出电压,压电双晶并联型振动发电机具有较大的输出电流,但两者具有相同的最大输出功率。

In order to analyze the effects of bimorph piezoelectric connection on the force-electrical output characteristics of vibration power generator(VPG),and effectively improve the overall performances,considering the coupling effects of the mechanical-circuit in the mechanical side and the circuit-circuit in the electric terminal,finite element analysis of kinetic equations for VPG was inferred from piezoelectric constitutive equations.A coupled electromechanical finite element analysis(FEA) model of VPG with bimorph piezoelectric connection in series and in parallel was derived with ANSYS software by the formula.Then,the influence of different bimorph piezoelectric connections on the vibration characteristics and the electrical output characteristics of VPG with the same force was comparatively analyzed.Finally,optimization analysis of their electrical output power was imiplemented by adjusting the load resistance,which respectively got optimal load resistances and the maximum output power.The research's results show that VPG in parallel connection can get larger output current,while getting larger output voltage ill series connection;and although the optimal matching resistance of VPG with series connection is 4times the size of one with parallel connection,their maximum output power is same.