【摘要】 牵引电机轴承的动态刚度直接影响轨道交通转子系统的动力学性能与运行平稳性。针对现有测试方法难以兼顾多工况测量与非线性特征提取的问题，本文提出一种融合实测数据与理论模型的数模联合驱动方法，用于滚动轴承动态刚度的高精度测试。首先，基于滚动轴承刚度矩阵解析理论，建立五自由度拟静力学模型，系统考虑离心力、陀螺力矩及接触变形等非线性因素；其次，自主研制轴承动态刚度测试试验台，实现连续变载荷工况下轴承位移与受力的高精度同步测量；然后，构建融合实测数据与理论模型的参数优化目标函数，采用智能优化算法辨识轴承结构特性关键参数，最后由解析模型计算获得轴承动态刚度的精确解。试验结果表明：轴承动态刚度随转速升高呈现显著的“刚度软化”现象；轴向动态刚度随轴向载荷增加而明显增大，而径向动态刚度随径向载荷增加的变化趋势相对较弱。本文方法有效克服了传统线性拟合忽略非线性特征的局限，为牵引电机转子系统的动力学设计与运行稳定性评估提供了必要的理论依据与试验支撑。更多还原

【Abstract】 The dynamic stiffness of traction motor bearings directly affects the dynamic performance and operational stability of rail transit rotor systems. To address the limitations of existing testing methods in balancing multi-condition measurement and nonlinear feature extraction, this paper proposes a data-and model-driven method based on measured data and theoretical models for high-precision testing of rolling bearings’ dynamic stiffness. Firstly, based on the analytical theory of the rolling bearing stiffness matrix, a five-degree-of-freedom quasi-static model was established to systematically consider nonlinear factors such as centrifugal force, gyroscopic moment, and contact deformation. Secondly, a dynamic stiffness test rig for bearings was independently developed to achieve high-precision synchronous measurement of bearing displacement and applied force under continuously variable load conditions. Thirdly, a parameter optimization objective function integrating measured data and theoretical models was constructed, and an intelligent optimization algorithm was employed to identify key parameters defining the bearing structural characteristics. Finally, the accurate solution of the bearings’ dynamic stiffness was obtained through the analytical model. Experimental results indicate that the bearings’ dynamic stiffness exhibits a significant "stiffness softening" phenomenon with increasing speed; the axial dynamic stiffness increases markedly with increasing axial load, while the radial dynamic stiffness shows a relatively weak trend of variation with increasing radial load. The proposed method effectively overcomes the traditional linear fitting’s limitation of ignoring nonlinear characteristics, providing an important theoretical basis and experimental support for the dynamic design and operational stability assessment of traction motor rotor systems.更多还原