Multivariable gain scheduled control of two funnel liquid tanks in series

This paper presents a concept of the continuous-time gain scheduled 2DOF control for the nonlinear system of two funnel liquid tanks in series, based on linearization of nonlinear equations of the system about selected operating points. Discussed technique extends the idea of design via linearization approach. In order to achieve desired stability and performance requirements, a linear feedback controller is designed at each point. Based on this strategy, polynomial method is taken into account. Specifically, the exact pole placement method as well as weighting matrix, dividing weights among numerators of transfer function matrices of subcontrollers guarantee control quality. The parameters of the resulting family of linear controllers are scheduled as functions of reference variables, resulting in a single feedback matrix controller. The derived gain scheduled controller is implemented and applied on the illustrative nonlinear model of two funnel liquid tanks in series.