Research And Design Of Fractional Order Controllers Based On QFT Automatic Loop Shaping

Following the fractional order calculus coming to more and more research fields, the combination between control theory and it arouses scholars’study enthusiasm. The correlational studies proved that, using fractional order controllers always obtain better control performance than using the traditional integral order controllers, the design of fractional order controllers has become the hot research area recently. This article aimed at controlled plants with highly uncertainty and disturbance, combining with QFT and PSO, presents a kind of fractional order robust controllers design method—the design method of fractional order controllers based on QFT loop automatic shaping. The main research content as follows:Firstly, the paper introduces the history of fractional order calculus, and the application in some fields of science, gives the background knowledge of QFT and PSO, analyses the study situation of the fractional order operator approximation and the design of fractional order controllers in recent years.Secondly, the followings summarize the rudimentary knowledge of fractional order calculus, mainly research the approximate methods of fractional order operator, and using frequency response fitting method realizes the rational approximation of the complex fractional controllers.Thirdly, giving the structures and design ideas of PIλDμ controller, CRONE controller and fractional order lead-lag compensator, providing the parameters adjust objects toward this paper’s algorithm.Finally, the paper presents the constraint conditions and objective function, gives the main idea and procedures of the design method. Aiming at highly uncertainty and disturbance objects, using PIλDμ controller, CRONE controller and new fractional order controllers’ structure to prove the availability of this paper’s controllers tuning method, and gives simulating curves, which show that the controlled results achieve the performance index.