Teaching canal hydraulics and control using a computer game or a scale model canal

Irrigation is well known for being the largest water user, responsible for about 70% of the total amount of fresh water withdrawals. At the same time, this irrigation contributes for about 40% of the total food production and is vital for many regions of the world such as Western USA, Australia, Southern Europe, and many countries in Asia and Africa. Recent FAO figures indicate that, by the year 2030, food production will have to be increased by about 80% with only a possible increase of 12% of the water withdrawal. One unavoidable way of being able to reach this agenda is to reduce water demand by improving the hydraulic efficiency of irrigation schemes. Technical concepts involved in these modernization projects include open channel hydraulics and control engineering, which are usually taught in separate college curricula. Such projects are carried out in many places in the world, especially in developing countries, with the help of engineers, canal managers and decision makers. This paper presents two innovative teaching initiatives targeting this audience, with a view to present classical and modern techniques to improve the hydraulic efficiency of irrigation canals. One is based on a computer game using the SIC hydrodynamic model developed by Cemagref, France and the other one is based on a scaled canal located at the USBR Hydraulics Laboratory in Denver, Colorado, USA

H infinity observer for time-delay systems. Application to FDI for irrigation canals

This paper deals with the problem of fault detection and isolation for time-varying delayed systems. It consists to develop a $H_{\infty}$ observer that generates residuals sensitive to some faults and insensitive to others in order to detect and isolate actuator faults which can occur on the regulation gates of an irrigation canal. The observer design uses a simplified approximate model of the Saint-Venant equations and is formulated with delay-dependent Linear Matrix Inequality (LMI). Simulations done with a realistic model of a real canal show the effectiveness of the metho

Data assimilation for hydraulic state estimation of a development project

International audienceAssurer la sûreté hydraulique sur les aménagements du Rhône est la priorité pour la Compagnie Nationale du Rhône. Cela signifie qu'il est indispensable de respecter les consignes d'exploitation sur les aménagements. Pour la régulation automatique des aménagements, le calcul de la commande prédictive s'appuie sur les mesures en cote en certains points caractéristiques ainsi que sur les débits aux ouvrages. De ce fait, lors de pannes de capteurs ou bien lors de forts phénomènes transitoires (tels que des arrêts ou démarrages de turbines), la régulation est perturbée. Suite à la présente étude, la solution proposée pour corriger les observations et mettre à jour les lignes d'eau intervenant dans le calcul des commandes, est la mise en place d'une méthode d'assimilation de données de type filtre de Kalman. Cette méthode est optimale dans le sens où elle assure la minimisation de l'erreur d'estimation. Mais cela n'est pas suffisant pour certaines applications industrielles. C'est pourquoi les notions de détectabilité et de convergence ont été approfondies. Cette étude a permis de déterminer des conditions suffisantes qui assurent une erreur de l'estimation convergente vers une moyenne nulle. Pour tester la mise en place d'une telle méthode, celle-ci a été implémentée sur l'outil de test industriel appelé " plateforme de simulation ". Des exemples de scénarios habituellement difficiles pour les régulations automatiques, telles que la perte de capteur et l'arrêt brutal d'une turbine sont présentés. Ils permettent de démontrer l'apport de la solution proposée. / Ensure the safety of development projects of the Rhône is the priority of the Compagnie Nationale du Rhône. That means it is essential to respect the water levels at some set points along the river. To regulate its development projects, the computation of the predictive control is based on measurements at the characteristic points as well as flows at the hydraulic facilities. Thus, when failures of sensors occur or during strong transients (such as stopping or starting the turbines), the regulation process can be disturbed. Following this study, the new solution suggested to detect sensor defaults, to correct the observations and to update the water profiles involved in the calculation of control actions, is based on a data assimilation method (Kalman Filter). This method is optimal because it ensures minimizing the estimation error. But this property is not sufficient for our industrial application. This is why the notions of detectability and convergence have been studied into detail. This study has identified sufficient conditions that ensure the error of the estimate to converge towards a nil average. In order to test and validate such a method, it has been implemented into the industrial test tool called "simulation platform." Examples of usually difficult scenarios simulating a loss of sensor and an unexpected stopping of a turbine are presented in this document. It allows demonstrating the benefits of the presented solution

Gestion opérationnelle des transports d’eau dans les canaux et les rivières

Après une présentation générale historique des canaux d'irrigation, de leur importance stratégique et des évolutions récentes, nous définissons de manière plus précise les systèmes hydrauliques à surface libre auxquels nous nous intéressons dans cet article. Nous présentons leurs spécificités qui rendent leur gestion essentielle mais délicate. Nous précisons ensuite ce que nous appelons concrètement "gestion", avec différentes nuances, dont la gestion opérationnelle, et nous utilisons des concepts issus de la gestion industrielle pour mieux l'analyser. Enfin, parmi ces concepts nous détaillons celui des "machines" permettant de mettre en ½uvre cette gestion opérationnelle. / After a historical overview of irrigation canals, their strategic importance and recent trends, we define more precisely the free surface hydraulic systems we analyse in this article. We see that they have features that make their management difficult but essential. Then, we define more precisely what we call "management", with different levels, including "operational management", and we use concepts from production management to better analyze it. Finally, we detail one of these concepts: the "devices" used to implement the operational management

Static and dynamic data reconciliation for an irrigation canal

International audienceThis paper deals with the problem of fault detection and isolation in irrigation canals. We develop a method which combines static and dynamic data reconciliation for the validation of measurements, detection and isolation of sensors and actuator faults and reconstruction of missing data. Static data reconciliation uses static models at a regulation gate to validate measurements and detect sensor and actuator faults. It also enabled us to detect a drift in the stage discharge rating curve. The dynamic data reconciliation uses additional measurements and a dynamic model of the canal in order to validate measurements and detect faults and withdrawals. The combination of the two methods allowed us to distinguish between withdrawals and faults. Both methods are evaluated on measurements from a real irrigation canal located in the South of France

Automatic tuning of PI controllers for an irrigation canal pool

The paper presents a method to automatically tune decentralized Proportional Integral (PI) controllers for an irrigation canal pool. The Auto Tune Variation (ATV) method is based on a relay experiment, which leads to small amplitude oscillations of the canal pool. The test signal is automatically generated by a relay inserted in the feedback loop. The method automatically estimates the ultimate gain and ultimate frequency of the pool, which can be used to tune P, PI or PID controllers. This method does not require advanced automatic control knowledge and is implemented in SIC software, developed by Cemagref, which also incorporates a SCADA module for real-time control. The ATV method is evaluated by simulations and experiments on a real irrigation canal located in the South of France, for local upstream, local downstream and distant downstream controller tuning

Flatness-based control of open-channel flow in an irrigation canal using SCADA

Open channels are used to distribute water to large irrigated areas. In these systems, ensuring timely water delivery is essential to reduce operational water losses. This article derives a method for open-loop control of open channel flow, based on the Hayami model, a parabolic partial differential equation resulting from a simplification of the Saint-Venant equations. The open-loop control is represented as infinite series using differential flatness. Experimental results show the effectiveness of the approach by applying the open-loop controller to a real irrigation canal located in South of France

La régulation des canaux d'irrigation : caractérisation et classification

This article suggests and defines a characterisation of irrigation canal regulation methods, based on four criteria : considered variables (controlled, measured, and control action variables), logic of control, design method (structure and technique) and field implementation (configuration and device). Depending on the chosen criterion and partition rule, different classifications can be built from this characterisation. In conclusion, a structured characterisation table of the main published canal regulation methods is presented. / Cet article propose et définit une caractérisation des méthodes de régulation des canaux d'irrigation rencontrées dans le monde, basée sur quatre critères : les variables considérées (contrôlées, mesurées, et de contrôle), les logiques de contrôle, les méthodes de synthèse (architectures et techniques) et les mises en oeuvre (architectures et ouvrages). Il est ensuite possible, en s'appuyant sur cette caractérisation, de définir différentes classifications, en fonction du critère choisi, et d'une loi de partition. En conclusion, cet article présente un tableau de caractérisation structuré, regroupant les principales méthodes de régulation des canaux citées dans la littérature

Contributions de l'automatique, de l'hydraulique et de l'informatique à la gestion des systèmes hydrauliques à surface libre

This document, for the Habilitation to Supervise Research, summarizes 20 years of research and development at Cemagref for the management of free surface hydraulic systems.Ce document, pour l'Habilitation à Diriger des Recherches, résume 20 ans de recherches et développements au Cemagref pour la gestion des systèmes hydrauliques à surface libre

Le contrôle des canaux d'irrigation : pourquoi et comment ?

Extrait de documentThe objective of this survey paper is to review, structure and analyze the main concepts involved in the control of irrigation canals, and to illustrate them on a canal benchmark. After a description of the irrigation and water management contexts, we present the main lines of a classification of the canal control systems. Then, we present a simple benchmark example of an irrigation canal. We compare results obtained with manual operation and some well known control algorithms (PID, LQG and l1). This illustrates the type of advantages that can be obtained with automatic control and some of the tradeoffs to be addressed in the selection of a solution. This also illustrates the needs for theory, methodologies, design and simulation tools to select and tune these control algorithms. Although a large part of these developments are still at the research stage, more and more of these techniques have successful field implementations