Development and Test of a Mathematical Model for Automatic Pivot Weir Based on PID Control

In order to improve the performance of irrigation networks, provide higher flexibility levels and improve water delivery methods, application of automatic control systems is suggested. In the coarse of the present study, a mathematical model of automatic pivot weir as based on PID control logic in combination with ICSS hydrodynamic model is developed. The developed model was tested under high flow variations on standard canal number two ASCE. The slope of the canal is mild; it is 28 KM long, provided with 8 reaches each reach equipped with an orifice offtake along with a regulating structure at the end. Water level variation and performance indexes MAE and IAE were analyzed. The results indicated that maximum error in the worst conditions amounted to 4% which is appropriate within practical terms. Water deviation was corrected within a few minutes. Therefore, it could be concluded that the developed model for automatic pivot weir is able to properly control the water level in irrigation canals.