Modeling and Control of Pipeline Networks Supplied by Automated Irrigation Channels

Abstract

A model-based approach to control system design is developed for regulating the discharge flows at the outlets of a pipeline network supplied by an irrigation channel. The open channel is also controlled automatically to regulate the supply-point water level. The hydraulic pressure at the source of the network is therefore dynamic when flow load varies. Regulation of the piped discharge flows is achieved by adjusting outlet control valves on the basis of the specified flow demand and sensor measurements. A blend of feedforward and feedback control is proposed. The steady-state behaviour of a nonlinear distributed-parameter model of the network is used to determine the feedforward control action. The feedback control action is used to compensate for modeling error. The design of the feedback controller is based on a frequency-domain transfer function model of the system dynamics, and classical loop-shaping ideas. This model is obtained via the admittance matrix of linearized network equations. The synthesis of both centralized and decentralized feedback controller configurations is considered. Simulations that involve a nonlinear distributed-parameter model of the network dynamics are used to illustrate controller performance.