压电叠堆联接方式及低频发电特点的研究

Performance of Piezoelectric Stack for Energy Harvesting from Low Frequency Vibration

压电发电是一种新型的振动能量收集技术。论文推导并给出了压电叠堆在33模式低频振动时输出电压和功率的数学表达式,并分析指出了输出电压和功率与压电系数、压电片个数、压电片厚度、激振力、激振频率正相关,与电极面积和介电常数负相关;电学串联的压电叠堆可以输出较高的开路电压;电学并联的压电叠堆可以输出较高的输出电流和功率。文中设计了压电叠堆夹持装置和振动发电实验装置,在振动频率5Hz、激振力26N的情况下得到两片电学串联叠堆和并联叠堆的最大功率分别为0.14μW和0.4μW;实测输出电压随振动频率、电阻、压电片个数、振子厚度和电极面积的变化趋势与理论预测相符。

Piezoelectric energy harvesting is a new type technology of clean energy.The output voltage and power equations of piezoelectric stack in 33-mode low frequency vibration were derived,which shows that the output power and voltage are positively correlated to the piezoelectric coefficient,thickness and number of patches,load resistance,exciting force and frequency,yet negatively correlated to electrode area and dielectric constant.Besides,higher output voltage can be got from serial piezoelectric stack while higher current and power can be generated by parallel one.The results were verified by the experiments conducted on PZT-43 type piezoelectric stack with a novel holding device.The maximum output power of serial stack and parallel stack in two piezoelectric patches are 0.14μW and 0.4μW respectively under the conditions of 5Hz frequency and 26N force.The measured trend of output voltage changing with the vibration frequency,the number and thickness of patches and the electrode area correspond with theoretical forecast.