基于压电悬臂梁的铁路钢桁梁桥振动能量收集方案研究

Study of Vibration Energy Harvesting Schemes Based on Piezoelectric Cantilever Beam for Railway Steel Truss Girder Bridge

为了研究在铁路钢桁梁桥布设能量收集装置的最佳位置,了解其给桥梁健康监测系统供电的可行性,基于压电悬臂梁能量收集基本原理,以一座有砟轨道96m双线下承式简支钢桁梁桥为背景,进行铁路钢桁梁桥振动能量转化为电能的收集方案研究。首先以压电悬臂梁作为能量收集装置,基于机电耦合理论,得到可收集能量与桥梁加速度响应的关系;其次应用车-线-桥耦合振动理论,分析该桥在列车过桥时不同构件的加速度响应;然后根据其振动特性设计压电悬臂梁的参数,采用MATLAB编程求解桥梁不同位置的可收集能量;最后提出6种振动能量收集方案并对比分析。结果表明,桥梁不同位置处动力响应不同,需根据其振动特性设计压电悬臂梁的参数;桥面系尤其是横肋中点处,适宜布置能量收集装置,可收集的能量可以满足桥梁健康监测系统的最小能量需求。

To look for ideal locations to install energy harvesting devices in the railway steel truss girder bridge and examine the feasibility of using the energy harvesting system to supply electricity to the bridge health monitoring system,a 96-m through simply-supported steel truss bridge carrying ballasted double tracks was taken as the study background,to examine the ways of harvesting the electricity converted from vibration energy in the railway steel truss girder bridge based on the basic energy harvesting principle of piezoelectric cantilever beam.First,the piezoelectric cantilever beam was used as the energy harvesting device,following the electromechanical coupling theory to obtain the relation between the available energy and the bridge acceleration response.Then,the train-track-bridge coupling vibration theory was used to analyze the acceleration response of different components of the bridge when a train was passing.Moreover,the parameters of the piezoelectric cantilever beam were designed according to the vibration property and the MATLAB program was employed to calculate the amount of available energy at different locations.Finally,a number of six vibration energy harvesting ways were proposed and contrastively analyzed.The results show that the dynamic response at different locations of the bridge is different,and the parameters for the piezoelectric cantilever beam should be designed according to vibration property at different locations.The bridge deck,especially the central point of the cross rib,is regarded as the proper locations to install energy harvesting devices,where the energy available for harvesting can meet the minimum energy demand of the bridge health monitoring system.