Improvement And Simulation Research On Fractional-order PID And Fractional-order PID-GPC Algorithm On Time Domain

As a widely used controller,the PID regulator has the advantages of simple principle,wide application range and so on,however,many models of the system’s objects are complex,the traditional PID controller can not meet the control requirements that in controlling the nonlinear time variant system.Fractional order PID controller adds two adjustable parameters so that it is better than the traditional integer order PID controller, the controller design is more flexible,and it has more excellent control performance. Generalized predictive control (GPC) take multi step predictive output, and it needs to obtain a large mount of information, control the inverse matrix and compute the Diophantine equation, generalized predictive control has low realtime feature, so it is important to improve the generalized predictive control algorithm.This paper analyzes the use of fractional PID algorithm (FOPID) in the application of engineering practice, and it verified the superiority and practicability of the algorithm,it get inspired On the base of verified the FOPID control algorithm superiority and from the scholars that had studied all sorts of new algorithm process derive by the combine of the PID algorithm and model control algorithm,the paper improve the algorithm that named FOPID-GPC algorithm, the algorithm has the advantage of good stability that containted by FOPID algorithm, and has forecast function. This paper shows the specific derivation process of the algorithm, and take ed two typical systems of the double tank water level control system and the boiler superheated steam control system as an example,it used the improved algorithm and the two mathematical model of control system simulation in time domain analysis,the select of FOPID-GPC controller parameters on control performance, through Matlab simulation illustrates the FOPID-GPC algorithm has better control performance than the basic PID algorithm, GPC algorithm and PIDGPC algorithm. This paper attempts to apply the improved algorithm in tank liquid level control system and the boiler superheated steam system, to explore a new control algorithm in the application of engineering practice to lay a theoretical foundation.