基于磁力耦合径向拉-压激励的回转式压电俘能器研究

A rotatory piezoelectric energy harvester under the radial tension-compression excitation based on magnetic coupling is presented through a preflex piezoelectric vibrator. The forming theory and method of the capability for the radial tension-compression excitation based on magnetic coupling and the energy generation of the preflex piezoelectric vibrator will be investigated theoretically and experimentally. The rotatory piezoelectric energy harvester has the advantages of high reliability, wide frequency band, small axial space, and so on. The energy harvester is suitable for the self-powered sensor monitoring system of rotating structures in the fields of the aviation/spaceflight and large equipments. The main research contents of this item are as follows. Firstly, the dynamics/kinematics models of the rotatory piezoelectric energy harvester will be established according to the coupling relationship among the machanical and electrical systems. On this basis, computer simulation will be utilized to obtain the nonlinear coupling property of the magnetic field, the influence law of magnetic coupling action on the performance of the excitation force and the relative-motion relationship of the mechanical components, and the optimal matching relationship of the system elements. Secondly, the radial vibration shape and the energy-generation property of the preflex piezoelectric vibrator will be studied. The influence of the structures/parameters of mechanical unit and electrocircuit-types/element-parameters of electrical unit on the energy conversion capability as well as energy conversion efficiency of the rotatory piezoelectric energy harvester will be analyzed. Based on this, the key factors restricting responding speed and orderly radial-reciprocating vibration of the preflex piezoelectric vibrator will be picked out. At the same time, the essential principle for the energy harvester to produce electric energy at wide bandwidth will be found out. According to the above research results, two kinds of rotatory piezoelectric energy harvester will be fabricated using various sorts of piezoelectric vibrators with different materials and configrations. A series of experiments on the test prototypes will be carried out in order to obtain the optimal excitation schemes, mechanical structures,and energy harvesting methods. Finally, over eight rotatory piezoelectric energy harvester as well as the key parameters/technology for their design/fabrication will be completed and provided.

提出利用磁力耦合拉-压激励预弯压电振子并使之产生沿旋转体径向伸缩振动发电，研究这种磁力耦合径向拉-压激励及发电能力的形成理论与方法，进而构造高可靠性、宽频带、轴向占用空间小的新型回转式压电俘能器，用于航空航天/大型机械等非结构环境中旋转体的自供电传感监测。主要内容：统筹考虑俘能器系统要素间耦合关系，建立系统动力学/运动学模型，通过模拟仿真获得磁场非线性耦合特性及其对激振力和部件相对运动关系的影响规律、以及合理的系统参数匹配关系；研究压电振子的径向振动形态及其能量转换特性，分析机械单元结构、电控单元电路形式/器件参数等对发电能力/效率的影响规律，提取制约预弯压电振子动态响应速度及有序径向往复振动的关键要素，揭示磁力耦合拉-压激励形成宽频带发电能力的本质机理；进行两类回转式压电俘能器样机制作与试验，获得最优激励方案、机械结构及能量回收方案；试制样机至少8台，提供设计方法及关键制造技术参数。

本项目针对现有旋转式压电俘能器可靠性低、转速适应性低、发电能力弱等弊端，以磁力耦合径向拉-压激励下预弯压电振子伸缩振动的工作机理与内在规律为研究对象，目的是通过磁力耦合拉-压激励预弯压电振子并使之产生沿旋转体径向伸缩振动发电，建立了压电俘能器在旋转磁铁激励下一般周期力的数学模型，开展了预弯梁压电振子的理论与仿真分析，获得了磁力耦合下预弯压电振子的初始工作位置对压电能量收集器的影响规律，试验得到了旋磁激励下弯曲压电振子的发电特性，在此基础上进一步探究了旋磁激励式压电预弯梁俘能器机理并通过试验获得了俘能器输出性能的影响规律，项目执行期间，课题组成员在原有实施方案基础上又提出了多种新结构新原理的旋磁激励式压电俘能器，包括：磁力夹持的旋磁激励压电俘能器、可调频旋磁激励式压电发电机、基于压电简支梁拉伸调频的旋磁激励式发电机、错位旋磁激励式压电俘能器等。四年来，本项目研究成果已经在国内外公开发表学术论文17篇，其中SCI检索期刊7篇、EI检索期刊8篇（1篇录用），获得发明专利17项、申请发明专利5项，3项专利技术转让66万元，国际会议分组报告2次，培养硕士研究生4名，依托本项目2016年项目负责人获得国家公派出国留学资格赴英国南安普顿大学访学一年，项目负责人也由副教授晋升为教授，并获聘本校“双龙学者”特聘教授。