A Hierarchical Architecture for the Coordination of an Ensemble of Steam Generators

This work presents a hierarchical architecture for the optimal management of an ensemble of steam generators, which needs to sustain jointly a common load. The coordination of independent subsystems is provided by a multi-layer control scheme. A high-level optimizer computes the optimal shares of production to be allocated to single generators. At medium level, a robust tube-based Model Predictive Control (MPC) is proposed to track the time-varying demand of the ensemble using a centralized, but aggregate model, whose order does not scale with the number of subsystems. At low level, decentralized controllers are in place to stabilize the internal boiler pressures. The control architecture enables dynamically the modification of the ensemble configuration and plug and play operations. Simulation results are reported to demonstrate the potentialities of the proposed approach.