The natural frequencies corresponding to the particular mode shapes of a large turbo-generator must not be in the resonance region before delivery. Different parameters may clearly affect these dynamic characteristics. Different from other studies, this paper introduces a method for obtaining the inherent characteristics of end winding in a short period of time under multiple simultaneously changing parameters. The proposed process is based on the response surface method (RSM). In this method, the main concerned natural frequencies were taken as the critical index to describe the dynamic behaviors of the end winding, with which the mathematical relationship between the dynamic characteristics and design variables was analyzed. First, the stiffness of the rings, stiffness of the radial braces and number of pins bonded to the radial braces were used as samples for orthogonal experimental design. Then, the natural modes and frequencies of 25 different samples were acquired by conducting modal analysis with ABAQUS software. Utilizing these dynamic results, a second-order polynomial response surface model was established to describe the relationships between natural frequencies and these three different parameters. Then, the quality of this model was verified by calculating the valuating indexes for comparison with support vector regression (SVR). With the response surface model, the variation regularities of the natural frequencies and modes due to the above parameters were discussed. The method proposed in this paper can enable natural frequencies in the whole design space to be quickly determined without finite-element analysis, greatly improving the development efficiency and laying a foundation for dynamic response prediction during normal operation with different parameters and additional large turbo-generator stator end winding optimization.

与大型涡轮发电机的特定模式形状相对应的固有频率在交付前不得处于共振区域。不同的参数可能会明显影响这些动态特性。与其他研究不同，本文介绍了一种在多个同时变化的参数下，在短时间内获得端部绕组固有特性的方法。建议的过程基于响应面方法 (RSM)。该方法以主要关注的固有频率作为描述端部绕组动态特性的关键指标，分析了动态特性与设计变量之间的数学关系。首先，环的刚度，径向支架的刚度和连接到径向支架的销钉数量被用作正交实验设计的样本。然后，通过ABAQUS软件进行模态分析，获得了25个不同样品的固有模态和频率。利用这些动态结果，建立了二阶多项式响应面模型来描述固有频率与这三个不同参数之间的关系。然后，通过计算与支持向量回归（SVR）进行比较的评估指标来验证该模型的质量。利用响应面模型，讨论了由于上述参数引起的固有频率和振型的变化规律。