具有不可微输入信号的改进型重复变结构控制

Modified repetitive VSC with nondifferentiable input signals

针对一类具有结构不确定性和周期性外部扰动的非线性系统,提出了一种改进型重复变结构控制(modified repetitive variable structure control,MRVSC)算法。在传统积分滑模面的基础上构造了改进型积分滑模面(modified integral sliding mode surface,MISMS)。基于MISMS,采用Lyapunov方法设计的MRVSC算法保证了非线性系统的运动轨迹在有限时间内到达MISMS并保持在MISMS上,并且使得滑模动力学系统变为重复控制系统。根据重复控制系统的稳定性条件及灵敏度函数选择MISMS的参数。仿真结果显示,与传统积分滑模控制算法进行比较,MRVSC算法使得非线性系统具有更好的跟踪性能。

A modified repetitive variable structure control（MRVSC） scheme is proposed for a class of nonlinear system with state-dependent model uncertainties and periodic exogenous disturbance.A modified integral sliding mode surface（MISMS） is constructed based on the traditional integral sliding mode surface.The MRVSC law designed by using Lyapunov theory guarantees the nonlinear system trajectory reaches the MISMS in a finite time interval and keeps up here thereafter,meanwhile,it makes the sliding mode dynamic become the repetitive control system.The parameters of the MISMS are selected on the bases of the stability condition and the sensitivity function of the repetitive control system.By comparing with the traditional integral sliding mode control scheme,simulation results show that the proposed scheme can provide a better tracking performance for the nonlinear system.