Detection of oscillations in control loops in irrigation channels

Oscillation in irrigation channels have many undesired consequences such as increased erosion on channel banks, reduced level of service to farmers, increased wear and tear on mechanical equipments, etc. It is therefore important to detect oscillations early. In this paper computationally inexpensive algorithms for detection of oscillatory control loops are applied to operational data from six consecutive pools of an irrigation channel. The algorithms performed well and detected the control loops which gave oscillatory responses. Moreover, the controller which caused the oscillations was also identified. As there can be many control loops in an irrigation channel, methods which are able to detect and locate the cause of oscillations are of great value in the operation of irrigation channels.