双杆结构双稳振动能量收集装置研究

Research on a Bistable Vibration Energy Harvesting Device with Double⁃Bar Beam

本文基于双杆梁的振动结构,提出一种新型能量收集装置,用于满足小功率的工作需求.首先,建立双杆梁振动能量收集装置的机械和电气模型,研究该系统的能量收集原理.针对上述结构,通过梁的总势能的变化曲线来研究该结构在不同初始状态下越过势垒的临界加速度,为后续激励加载提供参考依据.其次,应用拉格朗日方程推导出能量收集结构的振动方程,对该系统在谐波激励下的响应进行研究;实验装置通过粘在杆件表面的压电片与适配器与计算机连接,并用谐波激振实验验证解析法得到的结果,结果显示两者的变化趋势相同.最后在随机载荷激励下揭示了该能量收集装置平均功率与噪声强度之间的关系,噪声强度在0~2.5范围内,平均功率在15 pW之内.通过以上分析验证了该能源收集结构满足pW功率下工作的设备要求.

Based on the vibration structure of double-bar beam,a novel energy harvesting structure is proposed to meet the requirements of low power equipment.Firstly,the mechanical and electrical models of the double-bar beam vibration energy harvesting structure are established to study the energy harvesting mechanism of the system.For the above structure,the critical acceleration of the structure across the potential barrier is studied through the change curve of the total potential energy of the beam,which provides a certain reference for the subsequent excitation of loading.Then,the vibration equation of the mechanical system is derived using Lagrangian method,and the response of the system under harmonic excitation is studied.The experimental device is connected to an adapter and a computer via a piezoelectric piece glued on the surface,and the results obtained by the analytical method are validated by the harmonic excitation experiments.The results show that the theoretical and experimental approaches render consistent tendency.The relationship between the average power of the energy harvesting device and the noise intensity is revealed under the random load excitation.The noise intensity ranges from 0 to 2.5,and the average power is within 15 pW.It is verified that the energy harvesting structure can meet the requirements of sub-milliwatt power equipment.