磁悬浮机床主轴的自由递阶变结构控制

VARIABLE STRUCTURE CONTROL OF AMB MILLING SPINDLE

研究了变结构控制方法在磁悬浮主轴系统中的应用 .以铣削过程作为外界扰动 ,建立了主轴 -磁轴承系统动力学模型 ,设计了自由递阶变结构控制器 .仿真结果表明 ,该控制方法对于由阶跃、冲击以及切削等外扰动引起的主轴振动具有很强的抑制能力 ,对系统模型摄动及复杂加工过程亦有良好的适应能力 .

The application of the variable structure control (VSC) to the high speed milling spindle supported by active magnetic bearings (AMB spindle) is studied.The plant model including magnetic bearings,spindle dynamics and the cutting process is formulated and the variable structure controller is designed to attenuate the spindle vibration.Simulations show that the VSC strategy is robust against the external disturbances and model perturbation.In comparison with the PID controllers,the VSC enables much better dynamic performances to be achieved in terms of variation in the depth of cut.