Societe Du Canal De Provence Research Articles

Data Reconciliation on the Complex Hydraulic System of Canal de Provence

A data reconciliation module, based on the measurements from the hydraulic network, has been recently developed and implemented in the supervisory system of the Societe du Canal de Provence (SCP). The software has initially been used daily to check the measured flow on the main canal. The data reconciliation occurs just after the measurement process. The measurement network on the hydraulic system includes many sensors subject to failure or deviation and is spread over a huge area. In addition, discharge and volume measurements in open-channel hydraulic networks are characterized by large uncertainties. The objective of the data reconciliation is to take advantage of information redundancy on a system to make a cross-check of real-time measurements. By using this information redundancy, a data reconciliation module allows detection of inconsistent measurements and measurement deviations and provides corrected values whether the initial measurements are valid, biased, or invalid. A derived consequence is better scheduling of the maintenance of sensors. The results are corrected values for measured variables and proposed values for nonmeasured quantities. A statistical analysis of the results is performed. This analysis allows evaluation of the uncertainties attached to the estimated flows and volume values. It allows also detecting invalid measurements and drift of sensors and making decisions about which maintenance operations to perform.

Performance Assessment in the Management of ``Canal de Provence'', France

This case study presents the performanceassessment scheme of the network of canalsand pressurised pipes of the public andprivate company: ``Societe du Canal deProvence'' (SCP).According to a State Concession decree,this company is due to provide apre-established level of service to itscustomers, and be financially sustainable.Its technical and maintenance services haveinstalled a network of measurements anddata collection devices and defined aspecific set of performance indicators toverify achievement of these two goals.

Le rôle de la Société du Canal de Provence dans la gestion des ressources en eau de la région provençale

Today, the Provencal Region has largely overcome the risk of water shortages. Indeed, 40 years ago all the parties affected by a policy of good management of the region water resources as part of the general interest decided to work together in order to institute original solutions. These have proved pertinent and effective. The creation of the reserves needed to guarantee the satisfaction of water requirements associated with the development of all sectors of activity (urban, industrial and agricultural) was allied to the construction of major hydroelectricproduction facilities. The regional and local authorities involved together decided to execute and manage the facilities for conveying these resources to the points of consumption. To satisfy this common aim, they created the Societe du Canal de Provence et d'Amenagement de la Region Provencale (SCP), a regional development company within the meaning of French rural legislation, an original structure in many respects, particularly in terms of its status and its mission. All the actions undertaken by SCP in the framework of its public service mission result from a coherent and concerted plicy founded on the common interest, fundamental principle of a transparent and quality public, service run to satisfy economic performance and efficiency criteria. The economic management of the water resource applied on the scale of the schemes designed, constructed and operated by SCP is the combination and the result of a series of technical, financial, economic and management arrangements. Amid all the interrogations, reflections and recommendations encountered on the lasting responsibility of users, deprivation of public services, etc. which are at the heart of current debates, SCP, after 40 years of managing a water resource to the satisfaction of multiple users, stands out as an original solution which contributes to the on-going process of reflection.

Introduction of Smith Predictor into Dynamic Regulation

The architecture of Dynamic Regulation implemented in the Canal de Provence since 1971 consists of open loop/closed loop coupling. In addition, to take into account the interactions between the different reaches of a canal, Dynamic Regulation reports a fraction of the downstream check structure correction to the upstream check structures. While keeping the same well-tried logic, a research and development program has been pursued by the Societe du Canal de Provence (SCP) since the mid-1980s, in which the closed-loop module has been improved. A Smith predictor controller adapted to delayed systems has been introduced to control the down­ stream level of canal reach by adjusting the discharge upstream of the reach. A module has been introduced in the controller to adapt the control parameters on line and in real time after evaluation of the canal operating point (discharge and downstream level). This approach allows one to solve the hydraulic nonlinearity problem. The synthesis of the controller follows the so-called pole placement approach. At the end of the paper, this new controller's performances are analyzed as per the specifications of the ASCE Task Committee on Canal Auto­ mation Algorithms.

DYN2 Method for Optimal Control of Water Flow in Open Channels

A new method for the optimal real‐time control of water transport in open channels, called DYN2, is presented. This method was developed for controlling a class of water conveyance systems where so‐called dynamic regulation (DR), proposed by the Societe du Canal de Provence (France), is the basic control method. The DR concept is based on the heuristic policy, which compensates for downstream cumulative volume error. In DYN2, however, optimal control theory is applied to solve the water‐transport control problem more precisely than would be possible using the heuristic approach. Applying dynamic programming (DP) to DR, the DYN2 method was derived—thus the name DYN2. Advantages of DYN2 over DR are described. Both the DYN2 and DR have been applied on the Strezevo irrigation system (in Southern Yugoslavia, near Greece), resulting in the development of a state‐of‐the‐art computer‐based supervisory control and data acquisition (SCADA) system. In this system, a computer makes decisions based on either DR or DYN...

Etudes sur modèle réduit des dispositifs de dégazage dans les puits de mise en charge

Water pressure shafts connecting the canals to the operational tunnels are to be found in several hydro-electric developments designed and executed by the Societe du Canal de Provence. The water entering the shaft causes air emulsions which are driven to the bottom. However, it is absolutely necessary to prevent air bubbles from entering the tunnel in order to avoid a reduction in the volume of flow and hammering which can cause damage to the plant. The methods for deaerating the water, designed on a scale-model, depend on the energy content of the water entering the shaft and the extent of dissipation of energy within the shaft. The first example given is a shaft depth 47 m and diameter 10 metres with a rate of flow of 10 m3/sec and a maximum head of 27 metres. This shaft thus has a large capacity which ensures virtually complete dissipation of the energy of the jet and does not require a deaeration system. The second example given is a 19 m deep shaft whose diameter of six metres has been determined after having studied the velocity of a scent of bubbles. Tests performed on scale models have revealed that air emulsions entered the level at rates of flow of between 5 and 9 m3/ sec. The deaeration method adopted consisted of building a circular chamber five metres long and of the same diameter as the shaft at the entrance to the tunnel. The third example is a 13 m deep and 5 m diameter shaft, rate of flow 11 m3/sec. This facility has necessitated not only a deaeration chamber at the entrance to the tunnel but also a jet breaking floor installed in the middle of the shaft. The floor has made it possible on the one hand to break the energy of the fall and thus reduce the volume of air driven to the bottom of the shaft, and on the other, to prevent a vortex, which was occurring at maximum flow from reaching the tunnel. The tests undertaken revealed the need to install an additional deaeration chamber at the entrance to the tunnel to complete deaeration, which was not fully performed by the jet-breaking floor.