基于FKM标准的高压电器箱随机振动疲劳研究

Research on random vibration fatigue of high-voltage electrical box based on FKM standard

当地铁车辆运行时,其高压电器箱会受到随机载荷的作用,为保证行车安全需要保证其疲劳强度满足设计要求。针对某型地铁车辆在运行过程中出现的高压电器箱三位置开关处的铝板安装螺栓松动的问题,文章根据GB/T 21563—2018标准规定的载荷和FKM标准对高压电器箱疲劳强度进行评估,计算结果表明铝板的疲劳强度利用度大于1,疲劳强度无法满足FKM标准要求。通过对高压电器箱进行冲击试验,在纵向随机振动试验中铝板出现了开裂和螺栓松动现象,这验证了纵向随机振动仿真结果的准确性。基于仿真和试验结果,对高压电器箱结构进行改进设计,改进后的高压电器箱疲劳强度满足设计要求。

The high voltage electrical boxes on metro vehicles are subjected to random load during operation.In order to ensure operation safety,it is necessary to ensure that the fatigue strength of high voltage electrical box meets the design requirements.Aiming at the problem of aluminum plate mounting bolts at the three-position switch of the high voltage electrical box become loose during the operation of a metro vehicle,the fatigue strength of the high voltage electrical box is evaluated according to the standard load and FKM provided in GB/T 21563—2018 standard.The calculation results show that the fatigue strength utilization of aluminum plate is greater than 1,and the fatigue strength cannot meet the requirements of standard FKM.Through the impact test of the high voltage electrical box,in the longitudinal random vibration,the aluminum plate cracked and the bolts become loose,which verified the accuracy of the longitudinal random vibration simulation results.Based on the simulation and test results,the structure of the high voltage electrical box is improved.After the improvement,the fatigue strength of the high voltage electrical box meets the design requirements.