A method to coordinate decentralized NMPC controllers in oxygen distribution networks

This paper deals with the optimal operation of large scale systems composed by local processes liked by shared resources. A decentralized architecture plus a coordinator, which guarantees the satisfaction of the global constraints of the process, is presented. The decomposition of the control problem into smaller ones is based on Lagrangean decomposition and on price coordination methods to update the prices. A coordination method that allows formulating the price assignment as a control problem is presented besides a formulation based on market behaviour. Both approaches are driven by the difference between the total shared resources available and demanded by the local NMPC controllers. One advantage of this approach is that in the low layer only requires adding an extra term in the cost function of the existing NMPC controllers. Moreover, there is no communication between local controllers, only between each local controller and the coordinator.