In this paper, an impact-driven frequency-up converter for low-frequency vibration energy harvesting is proposed and investigated. Low-frequency vibration presents a significant challenge in vibration energy harvesting, and frequency-up conversion is one of several techniques used to tackle this concern. The proposed design is based on a high-flexibility Quasi-Concertina (QC)-based structure with a resonant frequency of ∼25 Hz, along with high-frequency piezoelectric cantilevers of a resonant frequency of ∼250 Hz. The mathematical model describing the operating sequence of the frequency-up conversion approach was initially developed. Experimental studies of the manufactured device were also conducted to validate the concept and to evaluate the performance and efficiency of the system under different frequencies, accelerations, and gaps between the QC structure and the piezoelectric cantilevers. The system achieved a peak voltage of 10 V (RMS voltage of 3.40 V) when subjected to vibrations of 2 g@25.5 Hz for an air gap of 2 mm. We also explored the possibility of using four piezoelectric cantilevers. Theoretically, the peak voltage dropped to 16 V; however, the RMS voltage increased to 8.44 V due to the slow damping of the generated output signal. The bandwidth was equal to 24–28 Hz for an acceleration of 1.8 g and 25–27.5 Hz for 1.4 g.

在本文中，提出并研究了一种用于低频振动能量收集的冲击驱动上变频转换器。低频振动对振动能量收集提出了重大挑战，而上变频是用于解决这一问题的几种技术之一。所提出的设计基于具有~25 Hz 谐振频率的高灵活性准六角形（QC）结构，以及谐振频率为~250 Hz 的高频压电悬臂梁。最初开发了描述频率上变频方法的操作序列的数学模型。还对制造的设备进行了实验研究，以验证该概念并评估系统在不同频率、加速度、QC结构和压电悬臂梁之间的间隙。当在 2 mm 的气隙下承受 2 g@25.5 Hz 的振动时，该系统实现了 10 V 的峰值电压（RMS 电压为 3.40 V）。我们还探讨了使用四个压电悬臂梁的可能性。理论上，峰值电压降至 16 V；然而，由于生成的输出信号的缓慢阻尼，RMS 电压增加到 8.44 V。对于 1.8 g 的加速度，带宽等于 24-28 Hz，对于 1.4 g 的加速度，带宽等于 25-27.5 Hz。由于生成的输出信号的缓慢阻尼，RMS 电压增加到 8.44 V。对于 1.8 g 的加速度，带宽等于 24-28 Hz，对于 1.4 g 的加速度，带宽等于 25-27.5 Hz。由于生成的输出信号的缓慢阻尼，RMS 电压增加到 8.44 V。对于 1.8 g 的加速度，带宽等于 24-28 Hz，对于 1.4 g 的加速度，带宽等于 25-27.5 Hz。