LMI based controller synthesis of an uncertain three tank system

Three tank system can be adapted to emulate many systems in process and aerospace industry. This paper presents synthesis of LMI based H
_∞
controller for uncertain three tank system. Uncertainties in parameters can arise due to imperfect knowledge of physical parametric values or from variations of these parameters during operation. A linearized affine dynamical model is derived with uncertain flow coefficients as varying parameters. H
_∞
controller is designed with multi-objective approach using derived affine model. Simulations are also carried out to assess the performance of controller against parametric variations/uncertainties simultaneously in the presence of input disturbances. The performance of designed controllers is compared with PI controller.