车载动力电池振动特性分析

Vibration characters of power batteries for new energy vehicles

车载动力电池是新能源汽车的能源供应系统,行车过程中的振动、冲击激励可能导致相应的故障,甚至安全事故。据此,将电池——车辆简化为五自由度系统并开展振动特性研究,通过拉普拉斯变换将振动微分方程化为五元一次方程组,利用Matlab符号运算获得传递函数表达式,并对螺栓联接电池组安装方案进行分析,获得其振动的幅频特性曲线,结果表明其敏感频率与路面激励、座椅频率相近,据此分析位移传递函数随安装刚度、阻尼变化曲线,依据该曲线可选择合理的安装刚度和阻尼。

Power batteries are energy-supplying system of new energy vehicles.Vibration and impact actuating during driving may induce fault,even safety accident.We simplified the batteries-car system as five degrees of freedom system in order to recognize its vibration characteristics.By deducing the vibration differential equations,and taking the Laplace transform,we transformed the second order differential equations into algebraic equations.The transferred functions was solved by symbolic algebra program of Matlab,and the vibration characters of batteries,which were installed by bolts,was analyzed to gain its amplitude-frequency curve.The results showed that its sensitive frequencies were close with uneven road surface and vehicle seat,which was harmful and necessary to improve.Finally,we gave the curve of displacement transfer function varying with stiffness and damping of installation,based on which a suitable stiffness and damping couldbe selected.