Abstract: Recently, the application demand for the traction battery frame of commercial vehicles has increased sharply, creating an urgent need for an accurate and efficient simulation method for fatigue durability analysis. The research is carried out based on OptiStruct and FEMFAT software. This paper apply the loads collected by the test vehicles to the traction battery frame, and use the modal stress recovery method to solve the fatigue damage of the structure. This method can accurately and efficiently complete the fatigue durability analysis of the traction battery frame, and the simulation results are consistent with the test results. This method has high application value in the development of new energy commercial vehicles.

Key words: traction battery; modal stress recovery method; OptiStruct; FEMFAT; fatigue durability

摘要： 近年来商用车动力电池框架开发与应用需求剧增，其疲劳耐久性能分析急需一套准确 高效的仿真方法。文章基于 OptiStruct 有限元软件及 FEMFAT 疲劳分析软件，将实车载荷加 载于商用车动力电池框架，运用模态应力恢复法求解结构的疲劳损伤。该方法可以准确高效 地完成动力电池框架的疲劳耐久分析，仿真和试验结果一致，该方法在新能源商用车开发中 具有很高的应用价值。

关键词: 动力电池；模态应力恢复法；OptiStruct；FEMFAT；疲劳耐久性