Research On Parameters Tuning Of Stair-like Predictive Controllers

Model predictive control (MPC), which appeared in industry in the 1970s, has been applied successfully in many process industries, and gained much interesting by the control theoreticians as well as control practitioners. In the last nearly thirty years, much progress has been made in theory research of MPC. By now, linear MPC theory is quite mature, and many issues have been addressed in nonlinear MPC formulation with academic success. MPC technology can be found in a wide variety of application areas, and both the number of applications and the size of the largest application are increasing. As the most promising advanced control algorithm, MPC's application in future will be optimistic.Tuning of parameters is an important step in the controller design process, since the closed-loop performance is related directly with values of the parameters. However, the MPC tuning is very difficult due to the complex structure of MPC, the implicit effect of parameters on closed-loop stability and performance, and the overlapped effect of the large number of parameters. The difficulty in tuning may degrade the control performance. Tuning MPC controllers for stable operation in the presence of constraints may be difficult, even when the process model is perfect. In order to achieve better performance, it is necessary to analyze the relationships among parameters and propose some efficient tuning methods.Stair-like MPC, which introduced reasonable constraints on control moves to reduce computational burden, has achieved many successful applications. Focused on stair-like DMC, the effects of parameters on closed-loop performance and relationships between parameters had been studied deeply, and then a multi objective optimization based tuning method for MPC was proposed. The main point and innovation of the thesis is listed as follows:1. The first-order plus dead time model, which is the most common model used to describe the main dynamic features of plants, was scaled by sample time. Both the effects of parameters on closed-loop performance of DMC and stair-like DMC were analyzed deeply. The stair-like factor changes the effect of parameters on closed-loop...