Robust PI decentralized control law for open-channel hydraulic systems

In this paper a PI decentralized constant-volume controller for open-channels is designed by minimizing the H₂ norm of a suitable transfer function matrix. Since the fundamental property which must be retained for all possible perturbations of the plant is stability of the feedback system, we have studied whether the proposed feedback design is robust in the face of output-multiplicative perturbations due to the low-frequency approximations and to the variations with respect to the reference configuration of uniform flow.