一类离散不确定时滞系统的输出反馈变结构控制

Output feedback variable structure control for a class of discrete uncertain systems with time-delay

针对一类离散不确定时滞系统,提出一种输出反馈变结构控制算法,该算法使系统状态无需完全可测.通过研究离散不确定时滞系统的简约型,基于LMI技术给出了滑模平面的设计方法,推导出了稳定的滑模面存在的充分条件,并将参数不确定性的影响等效为名义时滞系统的外界干扰,利用时延技术对干扰进行在线估计,从而抵消掉系统中的不确定性.采用离散趋近律的方法设计控制律,并通过仿真算例验证了所提出算法的有效性.

For a class of discrete uncertain system with time-delay, an Output feedback variable structure control algorithm is proposed, which does not need to full observe the system states by employing the algorithm. By studying nonsingular transform of the system, the sliding surface is designed based on linear matrix inequality （LMI） technique. The sufficient condition for the existence of stable sliding surface is gained. In addition, the influence of parameter uncertainties in system is equivalent to exterior disturbance of time-delay system. The disturbance is on-line estimated by using time-delay technique to cancel the effect of uncertainties in system. The controller is designed by using discrete approach law. The simulation results show the effectiveness of the proposed algorithm.