多稳态电磁俘能系统的非线性动力学实验研究

Experimental study of non-linear dynamics of multi-stable electromagnetic energy harvesting system

为克服共振式俘能器工作频带窄和压电式俘能器输出电流低等问题,设计了多稳态电磁式振动俘能系统。建立了系统的分数阶阻尼模型,通过实验揭示了多稳态电磁俘能系统的动态分岔、势能阱逃逸、高能态轨道和混沌运动等非线性行为。结果表明:采用庞加莱截面频闪采样算法和分岔图可有效刻画系统的非线性振动特性;利用多稳态电磁式俘能系统的非线性振动特性可显著增加输出电流并拓宽系统的有效工作频带。

The monitoring nodes of the wireless sensor network require an external power supply,and it costs a lot to build and maintain the power supply infrastructure.By using environmental vibration energy to supply power to the monitoring node,it not on⁃ly saves a lot of investment,but also saves energy and protects the environment,and thus has broad application prospects.Howev⁃er,the state-of-the-art resonant energy harvester has a narrow operating band,and the nonlinear approaches deliver small output power,which is difficult to drive the load circuit.In view of this,this paper proposes a multi-stable nonlinear electromagnetic energy harvesting system and conducts the related experimental study.The fractional-order damping model of the system is established.Ex⁃perimental research reveals nonlinear behaviors such as dynamic bifurcation,potential well escape,high-energy state orbit,and cha⁃otic motion.The results indicate that Poincarécross-section stroboscopic sampling algorithm and bifurcation diagram can effectively describe the nonlinear vibration characteristics of the system.The multi-stable electromagnetic system can be utilized to increase the output power and current(i.e.electrical load capacity)of energy harvesters as well as broaden the operating range of frequencies.