Development of Downstream Fuzzy Control System for Irrigation Canals

Limited water resources and poor performance of irrigation networks has attracted the attention of
experts to improve water delivery management by application of improved control systems. Improved
control systems in irrigation canals, because of complex hydraulic behavior, should be developed and
tested using mathematical and hydrodynamic models. Fuzzy theory has been widely and successfully
applied in several engineering control problems. In this research fuzzy theory has been applied for
control of irrigation canals. For the development of fuzzy control system, the ICSS hydrodynamic
model which could simulate unsteady hydraulic behavior in response of control systems in irrigation
canals is used. The performance of developed mathematical model of fuzzy control system is tested in
canal standard no. 2 introduced by ASCE, considering large flow variations. The performance of fuzzy
control system is evaluated using several indicators such as, maximum absolute error, cumulative
absolute error, and response time. The figures of flow, depth, and gate opening variations in time are
analyzed as well. The results show that by applying large flow variations, the maximum depth
deviation was 1.9%. The maximum response time for water depth to be stabilized within 1% range of
target depth was 1.8 minutes. The results indicate that the developed fuzzy control system was
successful in downstream control of irrigation canal and could be introduced for practical applications.