为了对望远镜次镜支撑系统动力学性能与风载响应进行理论分析，建立了正交弹簧模型，计算了风载功率谱的解析解。首先利用正交弹簧模型对次镜的支撑结构进行动力学理论建模，求得 2个相等的频率为 61.9578 Hz并使用有限元软件 MSC.Patran/Nastran进行了仿真，得到 2个相等的频率为 66.305 Hz，验证了简化的正确性；进而将其应用于风载功率谱分析，得出望远镜对风载的响应与频率的关系，以及风载作用的解析解和有效风载能量分布主要在 0.15 Hz以下的结论。

In order to study dynamic performance and wind load response of the telescope second mirror support system, the theoretical analysis of an orthogonal spring model, which calculates the wind load power spectrum, is introduced. Firstly this paper applies orthogonal spring model to the second mirror support structure dynamics modeling, getting two equal frequency points of 61.9578 Hz. And using the finite element software MSC. Patran/Nastran simulation, we get two equal frequency points of 66.305 Hz, which verifies the correctness of the simplification. And then, we use the wind load power spectrum to analyse the telescope therefore the relationship between the response to the wind load and the frequency is obtained, with the conclusion of that the wind load and the effective energy distribution are mainly in the domain of 0.15 Hz andbelow.