宽风速范围高效运行的风致振动微型压电能量收集器的研究

Self-powering of distributed sensor nodes in a big region is one of the key technologies of wireless sensor network. Exploring the method of converting local wind energy to electrical energy is a good solution to power the sensor nodes. First, the proposed work is intended to explore the mechanism by which the working range of the energy harvesters under the excitation of a natural wind is extended using the the nonlinear of the vibration system. The methods of wind energy aggregation and wind pressure amplification are studied. The micro piezoelectric energy harvesters using wind-induced vibration are designed to efficiently operate in a wide range of wind speed. And the design method is developed. Second, the fundamental mechanism of the three-way coupled interaction between the air motions, the structural vibration and electrical field is studied. An aero-mechanical coupling model and an mechanical-electrical coupling model are developed. The theoretical modeling method for the energy harvesters is proposed and the influence of wind field and characteristic parameters on harvester performance is analyzed. Third, the coupling relationship between the disciplines related to the energy harvesters is clarified. The approximation models of different disciplines, the decomposition strategies of multidisciplinary design optimization and the optimization algorithms are investigated. On this basis, the multidisciplinary design optimization method for the energy harvesters is developed. And the performance optimization problem of harvesters is solved. The objectives of this proposal are to explore the method and the theory of piezoelectric energy harvesting and to make the distributed sensor nodes self-powered. The proposed research can facilitate the development and utilization of the clean energy.

大范围内分布式传感器节点的能量自供给是无线传感器网络发展的关键技术之一，研究利用当地风力提供电能的方法是解决节点能量供给的有效途径。本申请拟探究环境风激励下利用振动系统非线性扩展能量收集器有效工作范围的机理，研究风能聚集与风压放大的方法，以提出宽风速范围高效运行的风致振动微型压电能量收集器的设计方法；研究能量收集器空气运动-结构振动-电场三者相互作用机理，在建立空气运动-结构振动耦合模型和结构振动-电场耦合模型的基础上，提出能量收集器的理论建模方法，并探究风场、特征参数对其性能的影响规律；分析能量收集器所涵盖的各学科的耦合关系，探究其各学科的近似模型、多学科设计优化求解策略与优化算法，并在此基础上提出该能量收集器多学科设计优化方法，解决收集器性能优化问题。本申请的研究旨在对基于风致振动的压电俘能方法及相关理论进行探索，以实现分布式无线传感器节点的能量自供给，并促进清洁能源的开发与利用。

随着无线传感网络、微电子无线通讯的发展，给各种微电子器件供能是迫切需要解决的技术问题，而利用环境中的风能发电给是解决微电子器件供能的有效办法。本项目为提高风能收集器的采集效率和机电转换效率，研究并提出了四款新型的压电风能收集器：风弦琴型风致振动压电能量收集器、浓缩风能压电能量收集器、基于叶片旋转式压电薄膜型能量收集器、基于屈曲梁的压电风能收集器。建立了悬臂梁式风致振动压电能量收集器风-结构振动-电场的多物理场耦合模型，分析了收集器的结构参数和材料参数等对能量收集性能的影响。建立了风弦琴型风能收集器的流固耦合、机电耦合有限元分析模型。进行了基于屈曲梁的压电风能收集器理论分析。提出了基于自适应模拟退火算法的风弦琴型能量收集器压电振子的优化设计方法，对压电振子进行了优化设计。分析了风弦琴型压电能量收集器腔体等结构参数对输出性能的影响，对高性能风弦琴型能量收集器进行了设计。对并联同步开关电感、自供能同步电荷提取能量收集电路进行了设计与仿真，获得了收集电路参数对电能回收性能的影响规律。搭建了低运行成本、易于操作、可无级调速的小型风洞以及微型风能收集器性能测试平台，为开展微型风能收集器研究提供了良好的试验条件。对不同结构、不同尺寸、不同材料的风致振动压电能量收集器进行了试验研究，获得了提高收集器性能的设计方法；试验研究了风弦琴型压电能量收集器各结构参数对输出性能的影响，对理论仿真结果进行验证；试验研究了浓缩风能收集器PVDF压电振子对输出特性的影响规律；试验研究了叶片旋转式压电薄膜型能量收集器的电输出特性，提出了提高该收集器性能的方法；试验研究了基于屈曲梁的压电风能收集器的输出性能。试验结果表明，所提出的收集器能有效地收集风能并具有较好的电输出性能。