Flatness-based control of open-channel flow in an irrigation canal using SCADA [Applications of Control]

This article applied a flatness-based controller to an open channel hydraulic canal. The controller was tested by computer simulation using Saint-Venant equations as well as by real experimentation on the Gignac canal in southern France. The initial model that assumes constant lateral withdrawals is improved to take into account gravitational lateral withdrawals, which vary with the water level. Accounting for gravitational lateral withdrawals decreased the steady-state error from 6.2% (constant lateral withdrawals assumption) to 1% (gravitational lateral withdrawals assumption). The flatness-based open-loop controller is thus able to compute the upstream water discharge corresponding to a desired downstream water discharge, taking into account the gravitational withdrawals along the canal reach.