Abstract Advances in energy harvesting techniques, along with low-power electronic devices open up the possibility of developing self-powered engineering systems. Most existing energy harvesters are constructed with beams such as cantilevers, fully-clamped beams and buckled beams. Here we present an attempt to add a new design dimension to the piezoelectric energy harvesters (PEHs) by exploiting a curved-beam structure. This design will be shown to dramatically improve the contemporary harvester performance. To establish an analytical base for curved PEHs, we take a variable-curvature unimorph as the general modelling object and derive its governing equations based on the Timoshenko beam theory. Using the mode expansion method with the consideration of boundary conditions and continuous conditions, we present analytical solutions of the electrical and mechanical response of the PEH. The model developed is verified via the finite element method and it can accurately estimate the modal response of the curved PEH. Prototypes are fabricated and tested to validate the analytical model and solutions. Furthermore, we comprehensively analyzed the key parameter effects including the length of the straight beam, thickness ratio and Young’s modulus on the performance of the PEH. The proposed analytical model provides an analytical guidance for composite arc-shaped PEHs with variable curvature and it also helps in the design and optimization of new PEHs.

中文翻译：

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分段弧形压电能量采集器分布参数机电耦合模型

摘要 能量收集技术的进步以及低功耗电子设备开辟了开发自供电工程系统的可能性。大多数现有的能量采集器都由梁构成，例如悬臂梁、全夹紧梁和屈曲梁。在这里，我们尝试通过利用弯曲梁结构为压电能量收集器 (PEH) 添加新的设计维度。这种设计将显着提高现代收割机的性能。为了建立弯曲 PEH 的分析基础，我们以可变曲率单压电晶片为一般建模对象，并基于 Timoshenko 梁理论推导出其控制方程。使用考虑边界条件和连续条件的模式展开方法，我们提出了 PEH 的电气和机械响应的解析解。建立的模型通过有限元方法验证，可以准确估计弯曲PEH的模态响应。制造和测试原型以验证分析模型和解决方案。此外，我们综合分析了直梁长度、厚度比和杨氏模量等关键参数对PEH性能的影响。所提出的分析模型为具有可变曲率的复合弧形 PEH 提供了分析指导，也有助于新 PEH 的设计和优化。制造和测试原型以验证分析模型和解决方案。此外，我们综合分析了直梁长度、厚度比和杨氏模量等关键参数对PEH性能的影响。所提出的分析模型为具有可变曲率的复合弧形 PEH 提供了分析指导，也有助于新 PEH 的设计和优化。制造和测试原型以验证分析模型和解决方案。此外，我们综合分析了直梁长度、厚度比和杨氏模量等关键参数对PEH性能的影响。所提出的分析模型为具有可变曲率的复合弧形 PEH 提供了分析指导，也有助于新 PEH 的设计和优化。