磁力调频压电电磁复合发电设计与实验

Design and experiment of piezoelectric electromagnetic hybrid broadband generator with magnetic force tuning

开展了基于环境振动发电作为微电源弥补传统化学电池供能缺陷的研究。基于非线性磁力调频开发了低宽频振动能采集压电电磁复合发电系统。介绍了发电装置工作原理;利用ANSYS和Ansoft Maxwell有限元分析软件仿真分析了压电和电磁发电的输出特性;最后,搭建了压电电磁复合宽频发电装置实验测试系统,测试了发电系统在磁力自调过程中的输出特性。实验结果显示：复合发电系统在谐振频率60Hz时输出开路电压峰值为5.8V,高于压电系统（5.5V）和电磁系统（410mV）独立发电的开路电压峰值。施加磁力拓宽装置后,当压电悬臂梁沿竖直方向上下移动0~15mm时,系统适应谐振频带拓宽为45~76Hz;悬臂梁沿水平方向平移0~30mm时,谐振频带拓宽为51~70 Hz。结果表明仿真分析与实验测试结果吻合很好。该宽频带能量采集技术可用于低频振动环境的能量采集,可在频变环境中为微型低功耗系统提供低电能。

This paper focuses on environmental vibration energy harvesting generator to provide low energy for a micro low-power system.A piezoelectric electromagnetic hybrid broadband power generator was developed based on nonlinear magnetic force tuning.The working principle of the power generator was introduced,and its output power characteristics by the piezoelectric system and electromagnetic system were respectively simulated with the software of ANSYS and Ansoft Maxwell.Then,an experiment system was set up to test the output power characteristics of the power generator with the magnetic force tuning.Experimental results indicate that the peak output open voltage from the power generator is 5.8Vat the resonance frequency of 60 Hz,which is higher thanthat of the piezoelectric system（5.5V）and the electromagnetic system（410mV）independently.When the natural frequency is adjusted with the magnetic force tuning,its resonance frequency band expands from 45 to 76Hz as the piezoelectric cantilever beam moves from-15 mm to 15 mm in the vertical direction.And the resonance frequency band expands from 51 to 70 Hz similarly as the cantilever beam moves from 0to 30 mm in the horizontal direction.The experiments show that the simulation analysis results are coincided with that tested results well.It demonstrates that the broadband energy harvesting system can use in low-frequency environment random vibration and can satisfy the demands of low-power of wireless sensor systems.