Energy harvesting has great potential for powering low-power wireless sensor nodes by converting environmental energies into the electricity. It can be widely used for real-time online industrial monitoring. Among different transducers, the variable reluctance energy harvester (VREH) has attracted much attention due to the great performance for the low-speed rotations. However, there is a lack of precise models for performance prediction. In this paper, a new modeling method for VREH is proposed to predict the output voltage. A combined Substituting Angle - Magnetic Field Division modeling method is presented to accurately model the magnetic permeance of the air–gap for the VREH. Then, the magnetic flux change in the magnetic circuit is derived to calculate the voltage response of the coil. The numerical and experimental results of voltage responses verify the effectiveness of proposed model with the maximum error of 4%. The influence of some key factors on voltage response is investigated, including the thickness of air–gap and tooth height. Moreover, power analysis demonstrates that the output power increases from 5.06 mW to 46.7 mW with the rotational speed from 100 rpm to 300 rpm.

通过将环境能量转换为电能，能量收集具有为低功率无线传感器节点供电的巨大潜力。它可以广泛用于实时在线工业监控。在不同的传感器中，可变磁阻能量收集器（VREH）由于低速旋转的出色性能而备受关注。但是，缺少用于性能预测的精确模型。本文提出了一种新的VREH建模方法来预测输出电压。提出了一种组合的替代角-磁场划分建模方法，以准确地模拟VREH气隙的磁导率。然后，导出磁路中的磁通量变化以计算线圈的电压响应。电压响应的数值和实验结果验证了所提模型的有效性，最大误差为4％。研究了一些关键因素对电压响应的影响，包括气隙厚度和齿高。此外，功率分析表明，随着转速从100 rpm到300 rpm，输出功率从5.06 mW增加到46.7 mW。