基于滑模轮廓控制器的直线电机精密运动平台轨迹跟踪控制

Trajectory Tracking Control for the Motion Table Driven by Linear Motors Based on Sliding Mode Contour Tracking Controllers

针对直线电机驱动的精密数控X-Y平台在加工非线性曲线轨迹时,存在轮廓误差精度与稳定性差的问题,提出了基于超螺旋滑模的轮廓控制与基于二次型最优化的位置控制相结合的控制策略。轮廓控制器选用等效误差量为状态变量进行控制器设计,使轮廓误差精度问题转化为等效误差控制问题。位置控制器利用二次型最优化系统频域因子分解的设计方法,不仅满足了位置跟踪的抗干扰要求而且使控制器设计解析化。仿真与实验表明:在非线性周期扰动与负载变化扰动下,所提出的创新性方法对于高精度轮廓加工具有良好的可行性和有效性。

For the poor robustness of direct drive X-Y servo systems in the nonlinear track processing, a method combining the position controller based on frequency domain optimization and the ultra spiral sliding mode contour tracking controller was proposed to ensure the robustness of control system. By choosing the equivalence error as state variables to design the contour controller, the problem of outline error precision was transformed into the stabilization of equivalence errors. A position controller was designed by using the method of frequency domain factor decomposition in the quadratic optimization system. This method not only met the requirement of anti-interference and made the controller design analytical. The results of simulations and experiments show that the designed controller has high contour tracking accuracy for the nonlinear disturbances and parametric disturbances.