Nowadays, the control designer has to deal with more and more complex systems, with a high number of dynamics, but also of actuators and captors, or even spatial structural constraints on the controller. This comes from the increasing complexity of industrial processes, the use of more and more efficient communication systems, and increasing performances requirements (optimization as global as possible).Even if decentralized control theory has benefit from numerous studies since the 70's, many problems are still opened. At the same time, efficient tools for analysis and synthesis have been developed, especially in the H2 and the H¥ context. However, application of such tools in the case of large-scale systems (composed most of the time of interconnected subsystems) may be difficult, even more if structural constraints are applied to the controller.Methodology is essential when the control problem of complex system is considered. To this end, this document focuses on the analysis of the interconnections of subsystems in order to choose the most appropriated structure for the controller. The choice of the criterion, and the global optimization of a H2 controller in a sequential manner are also considered. These methodological considerations are applied on an experimental web transport system.
