Electromagnetic energy harvesting has sparked the interest of researchers due to its promising potential in powering miniaturized electronic systems and wireless sensor networks. This paper focuses on a two-degree-of-freedom nonlinear electromagnetic energy harvester (2DOF-NEMEH) using a magnetic levitation architecture in rotational motion. The residual magnetic flux density is identified by the finite element method and gradient descent method, enabling a more precise description of the model. A dynamic model, accounting for the centrifugal force and the Stribeck friction in rotational motion, is established and validated by an agreement between experimental and numerical results. The mechanisms that can respectively enhance the energy output performance of the 2DOF-NEMEH in two different installation configurations are studied: One is to enhance the maximum output power through the negative damping of the stick–slip phenomenon for low-speed rotational motion, while the other is to broaden the operating frequency band through the combined effect of centrifugal force and 2DOF arrangement. The centrifugal stiffening effect and sudden-drop phenomenon are explored. Ultimately, optimization of the 2DOF-NEMEH achieved a maximum average output power of 4.6 mW and a wide operating frequency band spanning 0 to 600 rpm. Power supply tests for sensors are conducted on the optimized 2DOF-NEMEH, confirming its application potential.

中文翻译：

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旋转运动中的二自由度非线性电磁能量收集器


电磁能量收集因其在为小型电子系统和无线传感器网络供电方面的巨大潜力而​​引起了研究人员的兴趣。本文重点研究在旋转运动中使用磁悬浮架构的二自由度非线性电磁能量收集器（2DOF-NEMEH）。通过有限元法和梯度下降法识别剩余磁通密度，能够更精确地描述模型。通过实验与数值结果之间的一致性，建立并验证了一个动态模型，该模型考虑了旋转运动中的离心力和 Stribeck 摩擦力。研究了两种不同安装配置下分别增强2DOF-NEMEH能量输出性能的机制：一种是通过低速旋转运动的粘滑现象的负阻尼来增强最大输出功率，而另一种是通过低速旋转运动的粘滑现象的负阻尼来增强最大输出功率，而另一种是通过离心力和2DOF排列的共同作用来拓宽工作频段。探讨了离心硬化效应和突然下降现象。最终，2DOF-NEMEH 的优化实现了 4.6 mW 的最大平均输出功率和跨越 0 至 600 rpm 的宽工作频段。在优化后的2DOF-NEMEH上进行了传感器电源测试，证实了其应用潜力。