Design And Realization Of Fractional-order Controller Based On Process Control System

The concepts of fractional derivatives and integral were proposed three hundred years ago. Fractional calculus is the theory on the research and application of derivatives and integral of arbitrary order. It is a natural extension of the classical mathematics. Now, the application domains of fractional calculus have increased significantly. Since major advances have been made in fractional calculus in the last few years, the knowledge of fractional calculus begins to be applied in control theory and control engineering. It provides new landscape for control theory and control engineering based on integer-order differential equations. Now, the work is still giving its first step and, consequently, many aspects remain to be investigated.In this thesis, fractional-order control system is investigated from many aspects as followed:1. Several model sects of fractional-order control system are studied via simulation. And they are compared with the model sects of integer-order control system. At last some results are given.2. The methods of discrete approximate of fractional-order control systems are studied. And we given some compared results of different methods of discrete approximate. Performing the continued fraction expansion of the generating function corresponding to Al-Alaoui rule to obtain discrete approximation is better than the others.3. The performance of fractional-order controller is investigated. The effect of fractional-order controller's control parameters on control systems are investigated by qualitative analysis and simulation. In this thesis, the variation of the fractional-order controller's order and its effect on the fractional-order control systems are mainly investigated by qualitative analysis And some comparisons are done between fractional-order control system and integer-order control system.4. Based on math model, a fractional-order controller on process control system is designed. And parameters of fraction-order controller are gained by simulation. The performance of the controller is tested by the process control system designed by automatic laboratory.