悬臂梁压电振动能采集器的集总参数模型和实验验证

Lumped-Parameter Model and Experimental Verification for Cantilevered Piezoelectric Vibration Energy Harvester

压电振动能采集器是无线传感节点的一种理想电源,近年来受到广泛关注.考虑质量块和逆压电效应影响,建立了在基础激励作用下的悬臂梁压电振动能采集器的集总参数运动微分方程,得到了采集器固有频率的解析表达式.引入了2个反映压电层连接方式的常数,建立了对单压电层、双压电层并联和双压电层串联的悬臂梁压电振动能采集器均适用的耦合电路方程.求解以上方程,得到了简谐基础激励下的输出电压表达式.实验结果表明,固有频率和输出电压表达式的相对误差分别小于10%和20%.

Piezoelectric vibration energy harvesters have received great attention as an ideal electrical source for wireless sensing nodes. For a cantilevered piezoelectric vibration energy harvester, the lumped- parameter differential equation of motion was presented by considering the influence of proof mass and the inverse piezoelectric effect. The analytical expression of natural frequency was obtained according to the differential equation of motion. By introducing two coefficients which represent the connection configura- tion of piezoelectric layers, a uniform coupled circuit equation was established. This coupled circuit e- quation is applicable to the cantilevered piezoelectric vibration energy harvester with one piezoelectric lay- er, two series connected piezoelectric layers and two parallel connected piezoelectric layers. The analyti- cal expression of output voltage under harmonic base excitations was derived by solving the above equations. Experimental results show that the relative errors of the natural frequency expression and the output voltage expression are smaller than 10% and 20% , respectively.