自动消除主动磁悬浮轴承系统保护间隙机构的运动学分析

Kinematic analysis of auto-eliminating protective clearance device for active magnetic bearing systems

提出了一种可以在转子跌落后自动消除磁悬浮轴承系统中保护间隙的机构并介绍了其结构和工作原理。从运动学角度出发,分析了自动消除保护间隙轴承机构的自由度;对比了两种不同布局的机构的径向尺寸、支座摆动中心到连杆中销钉中心之间距离、连杆中销钉与销孔之间的间隙大小等主要参数对机构中支座的最大摆动角度的影响;设计并加工了相应的实物模型对理论结果进行了试验验证。研究结果表明,在相同的结构参数下,相比于支座摆动中心分布于连杆外侧的机构,采用支座摆动中心分布于连杆内侧机构中的支座能够获得更大的摆动角度。根据研究得到的结果给出了自动消除间隙保护轴承机构主要结构参数的设计准则,为自动消除间隙机构作为磁悬浮轴承系统保护轴承的设计和应用奠定了一定的基础。

An auto-eliminating clearance auxiliary bearing device which can automatically eliminate the protective clearance in active magnetic bearing system after rotor dropping is presented. Firstly, its mechanical structure and working principles are introduced. Secondly, the device＇s degree of freedom is kinematically analyzed. Moreover, for two different structures of devices, the influences of the devices＇ radial dimension, the distance between the swing center of support and the center of the pin hole in link rod, the size of the clearance between the pin and pin hole in link rod on the maximum swing angle of the supports in these two devices are compared. Finally, the maximum swing angles of those supports in each situation are experimentally verified. The results show that compared with the device with the structure that the swing centers of supports are located at the outer side of the link rod, supports in the device in which the swing centers are placed in the inner side of the link rod could swing to a greater angle. According to these results, the design criterion of the main structure parameters of auto-eliminating clearance auxiliary bearing is given. The results provide a theoretical basis for the design and use of this auxiliary bearing in active magnetic bearing systems.