Dynamic analysis and performance comparison of linear and nonlinear controllers applied to a nonlinear non-interacting and interacting process

Dynamic modeling and its control of two nonlinear processes are presented in this work. The processes emulate a clean water storage plant and are configured by interconnecting two tanks. According to the way, the tanks are interconnected, i.e., in cascade or in series, the dynamic behavior of the process changes from a non-interacting to an interacting system, both nonlinear. Three controllers (two linear and one nonlinear) have been designed and applied to the process. In order to evaluate the performance of the system, as a function of the controller applied, three figures of merit have been selected and compared. From the comparison results of these figures of merit, the advantages and drawbacks of each designed controller are identified. Finally, through simulation results, the feasibility of the system operation is verified.