Efficient energy harvesting from low and broadband frequency has always been a challenging problem. This paper proposes a solution in the form of an electromagnetic bi-stable vibration energy harvester (BVEH) with asymmetric potential barriers, in which the vibrator is attracted to the top magnet and repelled from the bottom magnet. By combining a magnetic spring and a mechanical spring, the BVEH achieves bi-stability with asymmetric potential barriers, enabling large amplitude vibration as the vibrator travels between the two potential wells. The traditional magnetic force model is modified to establish an electromechanical coupling model that accurately predicts the output of the BVEH. Numerical simulation results solved by the Runge-Kutta method show good agreement with experimental results. In addition, a prototype is fabricated and the system parameters are adjusted to achieve high-energy oscillation at the lowest frequency of 4 Hz. Under a sinusoidal excitation with an amplitude of 4 mm, the BVEH's bandwidth is expanded to 6 Hz, and the maximum power can reach 72.76 mW. Finally, the feasibility of the BVEH is demonstrated by powering different electrical appliances. The study provides a new technical approach for energy harvesting under low and broadband frequency vibration excitation.

从低频和宽带频率中高效收集能量一直是一个具有挑战性的问题。本文提出了一种具有不对称势垒的电磁双稳态振动能量收集器 (BVEH) 形式的解决方案，其中振动器被吸引到顶部磁体并被底部磁体排斥。通过结合磁性弹簧和机械弹簧，BVEH 实现了具有不对称势垒的双稳态，从而在振动器在两个势阱之间移动时实现大幅振动。修改传统的磁力模型，建立机电耦合模型，准确预测BVEH的输出。Runge-Kutta方法求解的数值模拟结果与实验结果吻合较好。此外，制作了样机并调整了系统参数，实现了4Hz最低频率的高能振荡。在振幅为 4 mm 的正弦激励下，BVEH 的带宽扩展至 6 Hz，最大功率可达 72.76 mW。最后，通过为不同的电器供电来证明 BVEH 的可行性。该研究为低频和宽带频率振动激励下的能量收集提供了一种新的技术途径。