Robust Flow Control of Single Input Multiple Outputs Regulated Rivers

Regulated rivers are used in many countries to sustain summer low flows and supply water for different users (drinking water, industries, irrigation, hydropower, salubrity). An upstream dam is used as storage, and the river is used as a channel to convey water-to-water users. Such systems are characterized by long and variable time delays between upstream and downstream points. This paper deals with the automatic control of such systems, where the action variable is the upstream discharge released by the dam, and the controlled variable is the downstream discharge of the river. As there are multiple outputs given by intermediate measurement points distributed along the river, the system is a cascade of single input, single output systems and is considered as a single input, multiple output one. A generic robust design synthesis is developed for internal model-based controllers. Simulations carried out on a nonlinear model of the Gimone River in the southwest of France show the improvement compared to present semimanual regulation.