基于Δ-Υ等效变换的SGCMG高速转子轴向振动特性分析及验证

Axial Vibration Analysis and Validity of High-Speed Rotor of Cantilever SGCMG Based on a Triangle-Star Equivalent Transformation

悬臂式单框架控制力矩陀螺(SGCMG)的轴向振动较为剧烈,频率成分也比较复杂;由于这种SGCMG结构是由众多串、并联,甚至桥联的弹性构件组成的,因此难以建立其精确的轴向动力学模型.首先通过Δ-Υ等效变换的方法,简化了高速转子的轴向串并联关系,进而计算出其轴向刚度;其次详细分析了系统激振源——预紧轴承各零部件的加工波纹所导致的预紧力的波动,并采用相互调幅的形式描述了该波动量;然后建立了高速转子的轴向动力学方程;最后通过数值仿真和实测结果的对比验证了分析的合理性和模型的有效性.

Cantilever single gimbal control moment gyroscope（SGCMG） excites severe axial vibration which includes some complex frequency components.Because the SGCMG structure consists of many elastic members with series and parallel,even bridging connection,it is very difficult to directly establish its accurate axial dynamics model.Firstly,the axial connection between components of high-speed rotor is simplified by using the method of equivalent transformation between the triangle and the star;thus,the axial stiffness of the rotor is calculated simply.Secondly,the exciting source for high-speed rotor vibration with the form of cross-amplitude modulation was analyzed which derives from preloading bearing processing error.Thirdly,the high-speed axial rotor axial dynamics equations were established.Finally,validity of the model is verified by comparing results of the numerical simulation based on the model and the experimental test for cantilever SGCMG.