Impacted-Region Optimization for Distributed Model Predictive Control Systems With Constraints
Shaoyuan Li, Yi Zheng, Zongli Lin
IEEE Transactions on Automation Science and Engineering
For a large-scale distributed system, distributed model predictive control (DMPC) is a method of choice because of its ability to explicitly accommodate constraints and to achieve good dynamic performance. In the design of a DMPC, guaranteeing stability with a strong global performance is known to be a challenge. In this paper, we consider a large-scale distributed system whose input is constrained to given sets in their respective spaces and propose a stabilizing DMPC design, where each
... em-based model predictive control (MPC) optimizes the cost function of the entire system over the region it directly impacts on. Consistency constraints and stability constraints, which bound the estimation errors of the interaction sequences among subsystems, are designed to guarantee that, if an initially feasible solution can be found, subsequent feasibility of the algorithm is guaranteed at every update, and that the closed-loop system is asymptotically stable. A key feature of the proposed DMPC is that it coordinates the MPCs of the subsystems by redefining the impact region of a subsystem according to the coordination strategy. Simulation results show that the performance of the proposed DMPC is very close to that of a centralized MPC. Note to Practitioners-The proposed method is designed for the systems which are controlled in a distributed structure. The aim of this method is to achieve a good performance of entire system within limited communication burden, and guarantee the recursive feasibility and asymptotical stability of entire system. To apply this method, the first step is to obtain the models of each subsystems. Then to configure the network information exchanging among these subsystems and construct the optimization problem of each subsystem. Finally, use the existing Quadratically Constrained Quadratic Program solvers to calculate the optimal control laws and applied these optimal control laws to the corresponding subsystems. This method can be used in large scale chemical processes, air condition systems for multi-zone buildings, distributed energy generation systems, etc. Manuscript Index Terms-Constrained control, distributed model predictive control, impacted-region optimization, large-scale systems, model predictive control, plant-wide optimization.