Model-Based Predictive Control Scheme for Cost Optimization and Balancing Services for Supermarket Refrigeration Systems

Abstract

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Distributed Model Predictive Control for Linear Constrained Systems Based on Time-Varying Terminal Sets

“…As can be seen from the foregoing DMPC optimization problem (13), the predictive model of the system (6) is known, however, the terminal constraint set X f i is unknown. Since X f i will lead to a large attraction field, hence, it is essential to design a suitable X f i to improve system performance.…”

“…Theorem 2: If the initial state z i (0) is feasible for optimization problem (13), then it remains feasible throughout the system evolution.…”

“…) is feasible solution of (13). Furthermore, the obtained cost by feasible solution and optimal solution are signed asJ(k + 1) andJ * (k + 1).…”

“…By implementing the algorithm proposed, the optimal control inputs and optimal states are obtained after solving the quadratic programming problem (13). Subsequently, the cost of the whole system can be calculated by (12).…”

“…If the controller fails, however, the entire system will not work properly [10], [11]. In addition, the load of online computing is increased by the huge scale of the system, and the performance of real-time is more difficult to guarantee [12], [13]. Later, the decentralized predictive control have been proposed by some research scholars.…”