控制力矩陀螺磁悬浮转子的指数趋近积分滑模控制研究

Research on Integral Sliding Mode Control with Exponential Approximation Law for Magnetically Suspended Rotor System of CMG

针对微重力、动框架等多源扰动下磁悬浮控制力矩陀螺磁轴承转子系统的强非线性、参数摄动及未建模动态等问题,开展控制力矩陀螺的磁轴承转子鲁棒控制研究。建立了磁轴承转子轴向通道动力学模型与电磁力工作点线性化模型,分析了系统参数摄动及未建模动态,并在此基础上提出了一种非线性系统指数趋近积分滑模控制方法,设计了含有电流及位移的积分滑模平面,采用指数趋近律与饱和函数抑制抖振实现到达阶段滑模控制律。实验结果表明:采用该方法可有效抑制滑模的抖振现象,参数摄动时系统具有较佳动态性能,同时在转子转动、框架工作时保证系统良好鲁棒性。

A robust controller for the magnetic beating system of magnetically suspended control moment gyroscope （MSCMG） is presented in this paper. The controller mainly deals with the problems such as the strong nonlinearity, parameter perturbation and modeling uncertainties in MSCMG. The axial dynamics as well as the lineatized electromagnetic- force models of magnetic bearings are developed. Besides, the parameter perturbation and modeling uncertainties are analyzed. Furthermore, a novel nonlinearity integral sliding mode controller is introduced based on the exponential approximation law. An integral sliding mode plane relating to current and position is designed; both exponential approximation law and saturation function are adopted to suppress the chattering phenomenon. Experimental results prove that the new method effectively suppresses SMC＇ s chattering problem and that the new method has good dynamic performance under parameter perturbation. Moreover, the control system possesses strong robustness to restrain multiple disturbances when both rotor and gimbal system work.