Feedforward control for the right margin of the main irrigation canal at the Begona district in Mexico

This paper describes the application of a distributed downstream control system to the right bank of the main canal of the Begona district. The right margin of the main canal is divided into 4 operational sections. The water level in the first three sections is controlled by changing the flow rate upstream of the section. The local regulator used has two components, feedback (level-regulation, local) and feedforward (flow, centralized). The feedback regulation algorithm is based on two proportional-integral regulators. The regulators keep the levels upstream and downstream of the section close to their reference profiles. The regulation algorithm is a modification of the BIVAL downstream control scheme. The use of flow rate as a control variable reduces the downstream propagation of upstream perturbations. The feedforward action is obtained from two decouplers. The first reduces the interactions among the controlled sections, since it transmits the downstream flow rate changes to upstream regulators, allowing the entire system to react simultaneously to any flow change. The second determines the flow rate evolution in the control structures needed to satisfy the future water demand through the canal. The simulation results obtained, in closed loop, illustrate how the feedback component compensates any variation in the water demand and the feedforward control component reduces the sections' interactions produced by known (future water requirements) and unknown (perturbations) demand variations. The control algorithm presented is an initial solution to the control of the right bank main canal of the Begona District.