多稳态振动能量俘获的非线性宽频机理及其优化控制

When supplying power to the embedded health monitoring, vibration energy harvesting is required to operate with long-term lifespan in stochastic variable ambient excitation. Nonlinear electromechanical coupling model, potential well function and bifurcation broadband mechanism of multistable energy harvesters are not completely investigated, and the transfer control of high-energy orbit is not successfully resolved. To overcome those issues, the electromechanical coupling mechanism for the variable condition of magnetic excitation, load and temperature is investigated to establish the nonlinear coupling model with nonlinear elasticity and hysteresis. The new calculating method of nonlinear potential well function is also presented to consider the effect of magnetic field distribution and structure parameter. Nonlinear system parameter identification for multistable energy harvesters under different excitation jumping frequency is proposed. Moreover, the steady and analytic solution of multistable energy harvesters are discussed to obtain the nonlinear bifurcation broadband mechanism. Performance optimization and control of nonlinear energy harvesters under stochastic noise and external disturbance are derived. Accordingly, the control strategy of driving the multistable system to high-energy orbits is proposed.. This project will be helpful to enhance the development of embedded health monitoring of human body and key structures such as engines, wings and blades.

振动能量俘获为嵌入式健康监测供能时，需要长期工作于随机多变的环境激励下，多种非线性耦合的力电模型、非线性势井的影响规律以及多稳态非线性分岔宽频机理尚未解明，同时，实现高能输出的多稳态非线性状态迁移方法未能很好解决。本项目针对这些问题，探究压电材料在磁场激励、应力载荷和温度多变环境下的力电耦合关系变化机理，提出考虑非线性弹性变形和迟滞的非线性力电耦合模型；研究空间磁场分布和结构尺寸等导致系统非线性势井不对称的影响因素，提出非线性势井函数的计算方法；研究多稳态俘能系统的稳态和解析解方法，提出不同激励跳跃频率下非线性系统模型参数辨识方法，获取多稳态非线性分岔高效宽频机理；推导出非线性俘能系统在随机噪声和外部扰动激励下的性能优化与控制方法,获得多稳态系统向高能轨道迁移的控制规律。.本项目研究对推动发动机、机翼和叶片等关键结构及人体的嵌入式健康监测技术发展，具有重要的理论和工程价值。

振动能量俘获为嵌入式健康监测供能时，需要长期工作于随机多变的环境激励下，非线性耦合的力电模型、非线性势井的影响规律以及多稳态非线性分岔宽频机理尚未解明，同时，实现高能输出的多稳态非线性状态迁移方法未能很好解决。本项目针对这些问题，提出了旋转磁耦合振动能量俘获方法,探究压电材料在磁场激励和应力载荷多变环境下的力电耦合关系变化机理，研究了考虑非线性弹性变形和迟滞的非线性力电耦合模型；研究空间磁场分布和结构尺寸等导致系统非线性势井不对称的影响因素，提出非线性势井函数的计算方法和增强其性能的策略；研究了多稳态俘能系统的稳态和解析解方法，提出了不同激励跳跃频率下非线性系统模型参数辨识方法，获取多稳态非线性分岔高效宽频机理；推导出非线性俘能系统在随机噪声和外部扰动激励下的性能优化与控制方法，获得多稳态系统向高能轨道迁移的控制规律。. 同时研究了轴承、人体运动嵌入式健康监测供能的理论模型和智能结构，设计了原理样机和实验系统，实验结果满足工程应用需求。本项目研究对推动高铁、风机和轴承等关键结构及人体的嵌入式健康监测技术发展，具有重要的理论和工程价值。