一种悬臂曲梁压电俘能器研究

Study on a Piezoelectric Curve Cantilevered Beam Harvester

提出了一种基于压电悬臂曲梁式能量采集器。采用曲梁式结构能在较小空间范围内提高压电体的表面积从而提高了能量采集效率,同时曲梁结构还能较好的适应微机电系统对压电俘能器严格的尺寸限制。该文假设该悬臂曲梁式压电俘能器仅处于面内振动状态,并定义了其位移模式。仿真结果表明,随着曲率半径的增大,压电俘能器的俘能性能随之提高,当基底材料的弹性常数和密度均较小时,即使没有集中质量的调节,该曲梁式压电俘能器仍能在较低的谐振频率下俘获周围的振动能量。

A new kind of piezoelectric harvester based on curved beam type was proposed. The curved cantilever increased the surface area of the piezoelectric layer with small space occupation and go without saying to improve the scavenging performance of the harvester. At the same time the curved shape also acclimatized the piezoelectric har- vester to the severe dimension restriction in the MEMS/NEMS. Based on the inplane vibration assumption the dis- placements of the curved beam were firstly defined. The variational theory was implemented to derive the curved harvester control equations. The finite element analysis method was used to solve the dynamic equations. The simu- lation results showed the open circuit voltage increased with the rise of the harvester curvature radius. The matrix material of the piezoelectric harvester was PDMS with very small elastic constants and density. This curved beam pi- ezoelectric harvester could work at low resonance frequencies even without the concentrated mass at the end of the curved beam.