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

Projet de modernisation et plateforme scientifique du canal de Gignac

Theoretical progress in the domain of open channel automatic control has been achieved in the last decades. Controllers are generally designed with the help of mathematical software and tested on computer simulation models. Nevertheless, a phase of real-time testing appears to be necessary before the full validation allowing wide spread implementations of given automatic controllers. This helps taking into account and solving problems linked to the physical limits of sensors or actuators or to usually neglected phenomenon such as communication delays, faults and model errors. The Gignac canal project aims at addressing this issue and sharing a research platform with diverse industrial and academic partners. It involves mainly the equipment of the canal with sensors and actuators, and an opened SCADA system. It has been designed to make possible the test of a wide range of control architectures and algorithms. The equipment also helps the canal manager facing strengthening management constraints. They appear with the strict application of new legislations which lead to diminish intake withdrawals and to modernize parts of the secondary network. The project associates in a scientific committee: the canal manager, research teams, engineering companies, Universities and Colleges. It helps transferring academic knowledge and focusing the experiments on problem solving and end-users' requirements. Universities and Colleges take benefit from the facilities for practical work for teaching programmes in hydraulics and automatics