轨道交通用高性能钹式压电俘能器研制及性能研究

At present, the studies on piezoelectric energy harvesters used in rail transit at home and abroad are still in their infancy. The energy harvested by the previous energy harvesters is relatively small, which pose great challenges for actual utilization in supplying electrical power. In this project, interconnecting the disciplines of structural engineering and electronic circuit, a kind of high performance cymbal piezoelectric energy harvesters used in rail transit with high bearing capacity and high power output are developed by integrating the characteristics of railway structure, the high power output characteristics of multilayer piezoelectric structure, the force amplification mechanism of cymbal metal caps, the high efficiency of synchronized switch harvesting on inductor circuit. Based on the piezoelasticity theory, theoretical analysis combined with ANSYS numerical simulation, OrCAD/PSpice circuit simulation and experiment research are used to investigate the effects of important structure parameters and circuit parameters on the mechanical property and energy harvesting performance. The interaction mechanism among the energy harvesters, the vehicle and the track structure are further analyzed. Subsequently, a coupled model of the whole system is put forward. Numerical analysis and experimental validation are performed to reveal the effects of vehicle parameters and installation location of energy harvesters on energy harvesting efficiency of the energy harvesters. Furthermore, the cooperative working mechanism between energy harvesters and wireless sensor is also explored. The studies in this project are expected to provide an effective approach for power supply of wireless sensor networks for health monitoring of railway infrastructure.

目前，国内外关于轨道交通压电俘能器的研究还在起步阶段，现有的俘能器俘获能量相对较小，难以满足实际供电需求。本项目将结合轨道结构的特点，融合钹型金属帽的力放大机制、多层压电结构的高功率输出特性以及同步开关电感电路的高效性，跨越结构工程和电子电路两个学科，研制一种适用于轨道交通的高承载力、高功率输出的高性能钹式压电俘能器，并基于压电弹性理论，以理论分析为主、ANSYS数值仿真、OrCAD/PSpice电路仿真和实验研究为辅，探究重要结构参数和电路参数对器件力学性能和俘能性能的影响；进一步，分析俘能器与车辆、轨道结构之间的相互作用机理，开展整个系统的耦合建模，完成数值分析和室内实验验证，揭示车载参数和器件安装位置对器件俘能效率的影响，并探究俘能器与无线传感器的协同工作原理。通过本项目研究，以期为铁路基础设施健康监测用无线传感器网络的电源供给提供一种有效途径。

针对现有轨道交通压电俘能器俘获能量相对较小，难以满足实际供电需求的问题。本项目一方面创建了分别以径向极化压电圆管和轴向极化压电圆环为基本单元的多种层状圆柱型换能器的力电耦合模型，系统探究了关键参数对器件性能的影响，并通过ANSYS数值仿真和实验研究验证了模型的有效性；在此基础上，设计了两种新型钹式俘能器，一种是由带孔的传统钹式金属帽与径向层状圆柱型换能器通过螺栓连接而成，另一种是由内嵌式钹型金属帽嵌入到阶梯型径向层状圆柱型换能器而成，并完成了实验研究，为开发高性能轨道交通俘能器提供新思路。另一方面以压电弹性理论为基础建立了单个压电叠堆的动力分析模型，全面分析了影响器件性能的关键因素，并进行了实验验证；在此基础上，设计了一种压电叠堆阵列型轨道交通俘能器，该器件融合多层压电结构和阵列型设计的高功率输出特性以实现大能量输出，且具有安装易、影响小、覆盖全、电压可调、适用广等优点，为铁路沿线无线传感器网络的电源供给提供了一种可能。此外，设计并制备了四种电路，开展了一些相关的探索性研究，比如圆柱型换能器的金属腐蚀监测，结构健康监测用球型压电智能骨料的设计理论等。