Study On The Improvement Of The Fractional Order PID Controller

At present,research of fractional order PID controller has become a hot topic in the control field. More and more research shows that, having two more adjustable parameters than integer order PID controller, the parameter tuning of the fractional order PID controller is more flexible and The control performance is more ideal.Currently,the majority of researches focus on the parameter tuning of fractional order PID controller while there are such few researches about its structure improvement.Combining with the current research results, researches about the improvement of the fractional order PID controller is conductingin this paper:(1) Based on the analyzing and simplifying of modified Oustaloup filter, a pseudo fractional order differential operator is proposed, and the pseudo fractional order differential operator is used to constitute the pseudo fractional order PID controller. Then, simulation experiments are conducted to test the control performances of the pseudo fractional order PID controller.(2) Drawing lessons from integer order fuzzy immune PID controller, combining fuzzy immune regulation with fractional order PID controller,the fractional order fuzzy immune PID controller is designed,which adds the adaptive function to the fractional order PID. Simulation results showthat,for fractional order non time delay systems, the fractional order fuzzy immune PID controller improves the control performance of fractional order PID controller.