时滞多输入离散变结构控制系统的趋近律方法

Reaching Law Method of Multi Input Discrete-Time Variable Structure Control Systems with Time Delay

研究了基于离散趋近律方法的变结构控制设计问题。借助于S型函数提出了的一种离散趋近律方法,应用到了时滞多输入离散系统。应用该趋近律设计的变结构控制系统,其特点是可以使系统的状态在原点稳定,且可有效消除由传统离散趋近律参数引起的抖振。最后的仿真例子进一步表明了本文方法对时滞离散系统的可行性与有效性。

The research of variable structure control system from home and abroad should be dated back to the 50s of last century,and have made great achievements in this field through unremitting efforts.The Russian scholars,as the excavators in the research field of sliding mode variable structure control,have obtained many achievements in the discussion of their advantages.Variable structure control has been developed to some extent in the field of production practice and theoretical research,but for its theoretical research field,continuous system is ideal for research and application of variable structure control.Because only the ideal sliding mode variable structure control in the continuous system can be constructed by the variable structure with the switching function to construct the equivalent sliding mode control.In the continuous system variable structure control theory system,the same study of discrete system shows that it cannot produce equivalent control of ideal sliding mode,but only produce quasi sliding mode control.Inevitably,in the production practice,on-line control and monitoring computer are discrete case,which lead to the majority of scholars to further expand the discrete variable structure control theory and practice field,it is a powerful driving force to promote the progress of the field.Based on the advantages of robustness and adaptability of sliding mode variable structure control,a new approach for reaching the law of time-delay multiple input discrete systems with time-delay is studied by using a new linear time-delay quasi sliding surface design scheme.First of all,a reaching law method based on S type function for multiple input discrete systems is presented,and a simulation example is given,which shows the advantages of the reaching law in multi input discrete systems.Secondly,based on the above reaching law method,a quasi-sliding mode variable structure controller is designed to ensure the state of the system can reach the quasi sliding mode in a limited time,and the detailed proof process is given.Finally,the simulation results show that the discrete convergence law proposed by the S type function is applied to the time-delay multi input discrete system.Finally,the simulation results show that using discrete reaching law,which based on the S function is proposed and applied to multi input discrete time-delay system,not only improves the dynamic quality of the system,and the system tends to the origin,to ensure stable performance of the system,but can also eliminate the chattering caused by conventional discrete reaching law parameters.