Xu Qiuyu, Gao Anran, Li Yigui, Jin Yan
College of Sciences, Shanghai Institute of Technology, Shanghai 201418, China.
State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
Micromachines (Basel). 2022 Apr 26;13(5):675. doi: 10.3390/mi13050675.
Piezoelectric cantilever beams are commonly utilized to harvest energy from environmental vibrations due to their simple structures. This paper optimizes a single crystal trapezoidal hollow structure piezoelectric cantilever beam vibration energy harvester with a copper substrate to achieve high energy density at a low frequency. Finite element analysis (FEA) is adopted to optimize the size of the copper substrate at first, and the piezoelectric energy harvester (PEH) is further optimized with a trapezoidal hollow structure under the optimal size of the copper substrate. The developed PEH with a trapezoidal hollow structure (L = 20 mm, L = 15 mm, and L = 40 mm), with a copper substrate of 80 mm × 33 mm × 0.2 mm, can obtain the best output performance. Under the condition of 1 g acceleration, the resonance frequency and peak voltage output were 23.29 Hz and 40.4 V, respectively. Compared with the unhollowed PEH, the developed trapezoidal hollow structure PEH can reduce its resonant frequency by 12.18% and increase output voltage by 34.67%, while also supplying a power density of 7.24 mW/cm. This study verified the feasibility of the optimized design through simulation and experimental comparison.
压电悬臂梁由于其结构简单，常用于从环境振动中收集能量。本文对一种带有铜基板的单晶梯形空心结构压电悬臂梁振动能量采集器进行了优化，以在低频下实现高能量密度。首先采用有限元分析（FEA）来优化铜基板的尺寸，然后在铜基板的最佳尺寸下，利用梯形空心结构对压电能量采集器（PEH）进行进一步优化。所研制的具有梯形空心结构（L = 20毫米、L = 15毫米和L = 40毫米）、带有尺寸为80毫米×33毫米×0.2毫米的铜基板的PEH，能够获得最佳的输出性能。在1g加速度的条件下，共振频率和峰值电压输出分别为23.29赫兹和40.4伏。与未空心化的PEH相比，所研制的梯形空心结构PEH可将其共振频率降低12.18%，并将输出电压提高34.67%，同时还提供7.24毫瓦/平方厘米的功率密度。本研究通过模拟和实验对比验证了优化设计的可行性。
