高速动车组牵引电机安装座服役环境与疲劳损伤分析

Service environment and fatigue damage analysis of traction motor mounting seat of high-speed EMU

高速动车组运行工况复杂,服役环境多变,其牵引电机安装座承受多点随机振动,易产生疲劳损伤。针对该问题,文章基于现场实测的不同运行速度下电机安装座处多通道振动环境数据,提出一种随机振动环境的振动谱归纳方法,得到了其服役环境振动谱,并通过三次多项式拟合外推了在450 km/h运行速度下的电机安装座振动谱;最后基于频域疲劳分析方法,阐述了电机安装座疲劳损伤随速度演化情况。研究结果表明,高速动车组牵引电机安装座服役环境振动谱与IEC 61373标准规定的振动谱差异较大,尤其在高频处,但振动能量两者值相差不大;随着速度增长,电机安装座疲劳损伤表现出指数型增长,但总疲劳损伤均小于1。

The operating conditions of high-speed EMU are complex and the service environment is varied.The traction motor mounting seat is subjected to multi-point random vibrations,which can easily cause fatigue damage.Aiming at this problem,this paper proposes a vibration spectrum induction method in random vibration environment based on the multi-channel vibration environment data of the motor mounting seat at different operating speeds measured on site.The service environment vibration spectrum is obtained,and the vibration spectrum of the motor mounting seat at operating speed of 450 km/h is extrapolated through cubic polynomial fitting;Finally,based on the frequency domain fatigue analysis method,the evolution of fatigue damage of the motor mounting seat with speed is explained.The research results indicate that there is a significant difference in the vibration spectrum of the service environment of the motor mounting seat of the high-speed EMU compared to the vibration spectrum specified in the IEC 61373 standard,especially at high frequencies,but the difference in vibration energy between the two values is not significant;As the speed increases,the fatigue damage of the motor mounting seat shows an exponential growth,but the total fatigue damage is less than 1.