惯性参数大范围变化机械伺服系统鲁棒跟踪控制

机械伺服系统在执行不同任务时,要求能适应不同质量或惯量的工作负载.而工作负载的改变会导致伺服系统惯性参数的大范围变化,目前常见的运动控制方法,如PD控制,基于干扰观测器的鲁棒控制等,对上述情况表现为系统不稳定或跟踪性能变差.对上述问题,本文假定惯性参数变化范围已知,提出一种新型的非线性控制方法,用滑模技术实现了系统对惯性参数变化和外部扰动的鲁棒稳定性,和跟踪性能,引入边界层技术避免了控制切换产生的抖振现象.用Lyapunov直接法对系统的全局稳定性给出了证明,并分析了系统的暂态响应.以直流电机高精度位置伺服系统为例的仿真结果表明算法的有效性.

Robust tracking control of mechanical servo systems with inertial parameters varying in large range

When implementing different tasks,mechanical servo systems must adapt to various working loads with different weight or inertia,which may lead to remarkable variation of servo system's inertial parameters.In such cases,motion control methods at present,such as PD control and disturbance observer-based robust control,exhibit instability or tracking performance declination.A novel nonlinear control scheme is proposed to deal with the above problems in known variation range of inertial parameters.The sliding mode technique is used for servo-system to achieve robust stability and guarantee transient response,and the boundary layer control is also adopted to avoid chattering introduced by control switching.The servo-system's global stability is then proved by using Lyapunov's direct method,and the transient performance is analyzed.Computer simulation results developed for a DC motor servo-system show the effectiveness of the proposed method.