Energy harvesting from rotational motion, such as vehicle tires and rotational devices, remains a challenge because of the difficulty of balancing the harvesting frequency range and the power-generation density and efficiency. Traditional energy harvesters using the mechanism of magnetic plucking and piezoelectric conversion cannot overcome the inherent disadvantages of the output power and the strictness of the application conditions. In this study, a low-frequency rotational electromagnetic energy harvester using a nonlinear magnetic plucking configuration is proposed. Using the novel structure to pluck a cylindroid generating magnet in each rotational motion, the resetting effect provides a new way to stabilize the output voltage and improve the energy harvesting performance. Two design factors for controlling the resetting effect were studied theoretically and experimentally. The finite element method based on the Maxwell stress tensor not only helps in understanding the magnetic field density distribution in the energy harvesting process but also reveals the resetting mechanism. Simulating a vehicle tire with a diameter of 0.6 m rotating at a speed of approximately 20 km/h, it was experimentally validated that the maximum average output power across all the rotating frequencies (0.5–5.0 Hz) reached 13.13 mW under certain excitation conditions in the experiment, which is increased by 215.9% compared with the harvester without the resetting effect. The great performance under different application conditions demonstrated that the proposed electromagnetic energy harvester has a great potential in energy harvesting from low-frequency rotational motions.

由于难以平衡收集频率范围与发电密度和效率，因此从旋转运动（例如车辆轮胎和旋转装置）收集能量仍然是一个挑战。传统的采用磁采和压电转换机制的能量采集器无法克服输出功率和应用条件严格的固有缺点。在这项研究中，提出了一种使用非线性磁拔结构的低频旋转电磁能量采集器。使用新颖的结构在每次旋转运动中拔出一个圆柱体产生磁铁，复位效应提供了一种稳定输出电压和提高能量收集性能的新方法。从理论上和实验上研究了控制复位效果的两个设计因素。基于麦克斯韦应力张量的有限元方法不仅有助于理解能量收集过程中的磁场密度分布，而且揭示了复位机制。模拟直径为 0.6 m 的汽车轮胎以大约 20 km/h 的速度旋转，经实验验证，在特定激励条件下，所有旋转频率（0.5-5.0 Hz）下的最大平均输出功率达到 13.13 mW。实验中，比没有复位效果的收割机提高了215.9%。