多质量块宽频压电能量收集器

A Multiple Mass Broadband Piezoelectric Energy Harvesting Device

为了提高压电能量收集器的工作频带宽度、降低其固有频率并提高收集效率,设计了一种多质量块宽频压电能量收集器。建立多质量块压电悬臂梁的理论模型,分析质量块位置对输出功率的影响;有限元分析质量块数量对输出电压和固有频率的影响;搭建试验台,对多质量块宽频压电能量收集器进行测试。实验测得:随着悬臂梁自由端质量块数量的增加其一阶固有频率由62 Hz降至28 Hz,工作频带宽度增加39.3%,输出功率由17mW增加至31mW,且整流后得到的功率是桥式整流电路的1.31倍。实验结果表明,随着质量块数量的增加,压电悬臂梁的一阶固有频率降低,频宽增大,输出功率增加,且新的能量收集电路的转换效率比桥式整流电路高。

A multiple mass broadband piezoelectric energy harvesting device is designed to broaden working band of the piezoelectric energy harvester,reduce its resonance frequency and improve the efficiency of conversion.The theoretical model of multiple mass piezoelectric cantilever beams is established to analyses the influence of the location of mass on the output power of piezoelectric cantilever.Then,the ANSYS is used to analyses the influence of the number of mass to the output voltage and resonance frequency of piezoelectric cantilever in ANSYS.An improved energy collection circuit is designed to compare with the classical circuit in this paper.Finally,an experimental system is built to measure the output voltage and output power of the piezoelectric cantilever beam.The experiment results show that with the increasing numbers of mass,the first resonance frequency reduced from 62 Hz to28 Hz,the power increased from 17 mW to 31 mW,the working bandwidth increased by 39.3% and the output power of the new circuit is 1.31 times higher than the classical one.So we can know that with the increasing numbers of mass,the first resonance frequency reduced,bandwidth expanded,output power decreased and the new designed circuit has a higher conversion efficiency compared with the classical one.