离散时间系统的变结构控制

VARIABLE STRUCTURE CONTROL OF DISCRETE-T ME SYSTEMS

研究离散时间系统的变结构控制问题．首先定义准滑动模态，给出详细的物理解释．然后讨论已有的到达条件。给出新的更一般的条件，即离散趋近律．对新定义的准滑动模态，解决了其稳定性并给出了切换函数．利用趋近律方法，给出了变结构控制的一般的设计方法，它既适用于单输入系统，也适用于多输入系统．

The variable structure control(VSC)of discrete time systems is studied in this paper. First of all, the quasi-sliding mode is defined and a detailed physical explanation to it is given. Previously established versions of reaching conditions are briefly reviewed and a new and more general version is given: the discrete reaching law. For this new definition of quasi-sliding mode its stability problem is proved meanwhile the linear switching function is determined.The VSC is obtained straightforward by the reaching law method, which is a general design method applicable both to single input and multiple input cases in a simple way.