驻极体静电能量采集器的结构优化

Structure Optimization of Electret-based Electrostatic Energy Harvester

摘要:

设计了基于高弹驻极体膜的可变电容静电能量采集器，通过有限元仿真模型研究了器件结构参数对输出功率的影响。制备并表征了优化结构的器件，实验和数值计算结果吻合。通过调节驻极体膜的预拉伸状态和振子的质量能够改变结构刚度和谐振频率，进而影响能量采集器的输出功率。结果表明：由大小和面电荷密度分别为30 mm × 10 mm和0.6 mC·m^-2的高弹氟化乙丙烯（FEP）驻极体膜、深度为4.0 mm的V型感应电极，以及质量为0.06 g振子构成的能量采集器，在1g（g为重力加速度）正弦加速度激励和20 Hz谐振频率下的输出功率高达870 μW。

Abstract:

A variable capacitor based electrostatic energy harvester including a high elastic electret film was designed. The effects of structure parameters on the output power of the capacitor were studied by finite element method (FEM) and the structure of the capacitor was optimized. The experimental data are in agreement with the FEM calculations. The resonance frequency and output power can be adjusted by pre-stretching electret film and varying seismic mass. For an energy harvester, consisting of a fluorinated polyethylene propylene (FEP) electret film with an active area of 3 cm² and a surface charge density of 0.6 mC·m^-2, a V-shaped counter electrode with a depth of 4.0 mm, and a seismic mass of 0.06 g, an output power of 870 μW was achieved at its resonance frequency of 20 Hz and sinusoidal acceleration excitation of 1g.