大型太阳电池阵模态试验方法

摘要

在大型太阳电池阵的研制阶段,需要进行大量模态试验以掌握结构的固有动态特性,进而指导设计和修正有限元模型.文章以大型太阳电池阵为研究对象,分别采用气浮方式和悬挂方式模拟自由边界条件,使用预紧力释放、MB大推力激振器和APS大位移激振器3种激励方法对其进行试验,并对各种模态试验方法所获取的试验结果进行了分析比较.研究表明:采用悬挂方式比采用气浮方式所测得的太阳电池阵侧摆频率更为准确；获取太阳电池阵模态参数行之有效的方法是先采用预紧力释放法得到固有频率,然后采用APS激振器激励方法得到振型；激振器激振杆横向刚度选择不当会影响模态测试结果,需选用横向刚度较小的柔性激振杆.%Modal tests are carried out in the development stage of a large solar array to find out its dynamic characteristics to improve the design and the finite element model. In this paper, the floating method and the suspension method are used, respectively, to simulate the free boundary. Modal tests are carried out by using the preload releasing method, the excitation methods with MB exciter and APS exciter, and the test results are compared and analyzed. It is shown that the swaying frequency measured by the suspension method is more accurate than that obtained by the floating method.