机电耦合激励下压电能量收集机理与电路研究

By use of piezoceramic to proceed energy harvesting from the ambient environment to support the micro-devices has been studied in recent years. However，there are still two major problems: difficulty to estimate the generated power and low efficient transformation & extraction electricity technique. This project is to study the mechanism of the piezoceramic under complex stimulation to establish the energy output analytical model for a piezoceramic, meanwhile its energy extraction circuit will be proposed. . In this study, we focus on: (1) the mechanism of the wall movement induced polarization under mechanical and electrical excitation, which lead to the study of piezoelectric energy transformation ratio under electric field. Improve the theory of using electromechanical coupling excitation to enhance the energy conversion and output of piezoelectric ceramics; (2) the complex dynamic excitation energy conversion model, with consideration of piezoelectricity failure, to estimate the random vibration in the environment induced amount of energy conversion. To obtain an electromechanical coupling excitation regulation to improve and optimize the transformation efficiency in consider of the wall movement; (3) the electromechanical coupling excitation energy extraction circuit, to make each module of the synchronous extraction circuit self-powered. By use of phase-shift synchronization and DC boost technology, the electric field and mechanical excitation should be mutual coupled, to achieve high-efficiency piezoelectric output..This study will help to improve the employment of self-powered MEMS design and its engineering application.

利用压电陶瓷将自然环境中的振动能量转化为可利用的电能，为低功耗电子设备提供能源的供电技术是近年来研究的热点。但复杂振动情况下的发电量预估、高效电能转化及提取技术依然是当前难题。本项目通过研究机-电激励对压电陶瓷极化作用机理，构建非线性能量输出模型，设计高效电能转化及提取电路。.研究内容包括：(1)机、电激励对压电畴壁极化作用机理，探究电场对压电能量转换效率的影响机制，完善利用机电耦合激励提高压电陶瓷能量转化和输出的理论；(2)复杂动态激励下能量转换模型，考虑压电失效，实现环境随机振动情形下电能转换预估，获得机电耦合激励调控手段，从畴壁极化角度提高和优化能量转化效率；(3)机电耦合激励下能量提取电路，完善同步提取电路各模块的自供电设计，利用相移同步和DC升压技术，使自身电场与机械激励相互耦合，实现压电能量的高效输出。.本研究在MEMS器件自供电理论指导和工程应用中具有重要意义。

利用压电陶瓷将自然环境中的振动能量转化为可利用的电能，为微型电子设备提供能源的供电技术是近年来研究的热点之一。本项目通过研究机-电激励对压电陶瓷极化作用机理，构建非线性能量输出模型，设计高效能量提取电路。通过对压电陶瓷进行参数表征，拟合静态极化曲线，构建压电陶瓷电场作用下静态极化模型；利用机电等效关系，分析机电激励下压电陶瓷极化非线性，获得压电动态能量输出模型，实现该模型宽频下的动态参数拟合；对压电陶瓷施加复杂动态激励，利用多元线性拟合理论，推导压电陶瓷机电转换系数函数，确定最佳激励区间，避免疲劳及退极化出现；根据压电方程，考虑激励参数变量，精确预估压电陶瓷电流输出；基于同步电荷提取技术，结合机电激励耦合作用机理，设计和优化压电陶瓷能量提取电路，提高能量输出功率；搭建振动俘能自供电无线传感网络节点，实现对环境的感知，验证了自供电系统的可行性。本项目对压电非线性模型的推广、驱动传感的应用探索和能量提取电路的设计为压电陶瓷的应用具有一定的有指导意义。