La régulation dynamique Sa mise en oeuvre au canal de Provence

Dynamic control. Example of the Canal de Provence

Directeur Adjoint des Services Techniques SOCIÉTÉ DU CANAL DE PROVENCE ET D'AMÉNAGEMENT DE LA RÉGION PROVENÇALE

Abstract

The Canal de Provence draws its supplies from the river Verdon, a tributary of the river Durance. Flow in the river is controlled by five dams built by "Electricité de France", all equipped with power plant. The Canal de Provence intake is on the supply canal of the last plant down-river. The Canal de Provence supplies water for irrigation, urban and industrial use. Basic components of this complex system are the following : 1/ High-capacity conveying facilities totalling open-canal and tunnel lengths of 100 km and 130 km respectively. 2/ Large-bore pressure mains. 3/ Final distribution networks. Irrigation, urban and industrial water requirements to be met vary with time according to different laws. The control system, therefore, must be capable of permanent optimal matching of supply to demand. The "dynamic control" method which has been adopted regulates the volumes of water through the canals and ducting, whilst "updating" reference volumes at regular intervals according to forecast consumption data. The system which has been designed on this principle transmits the necessary data from the canals and ducting to a remote operating centre, and appropriate gate or valve settings back to the network. Control works initially provided on the "Canal de Provence" were designed for operation on the "downstream control" principle. Dynamic control arrangements were tested and developed to operational readiness on an existing control structure scheduled for "modernization". All new control works were then designed for dynamic control and existing works converted accordingly. The following facilities are required for an operational dynamic control system : a) Remote transmission stations at suitable points along canals, pipes or tunnels, to "centralize" all data from instruments, control gates or valves. b) Availability of public Post Office communications facilities c) A remote control centre with a real-time computer programmed to produce control commands from a measured data input. The cost of the remote-transmission system amounts to roughly 3 per cent of the total construction cost.