Control of a Nonlinear Tank Process using Dynamic Matrix Controller

The level process is widely used in many process industries for storing the liquids for mixing purpose in sugar mills, as settling tank and for water treatment plants. Most of the chemical plants are multivariable processes which exhibit nonlinear behaviour due to the existence of interactions between the input and output variables. The level control of the cylindrical tank is difficult because of its nonlinearity. Linear PID (Proportional Integral Derivative) controllers are generally used in many industrial control systemsbecause of its simple structure and robustness, but whenit comes to the control of nonlinear and multivariable processes, the controller parameters have to be continuously adjusted in order to deal with the nonlinearities, uncertainties and interaction betweenthevariables.The major objective of this work is to control the level of a nonlinear tank process. This is achieved by modelling a nonlinear controller which can adapt to the nonlinear performanceof the process. To achieve this goal, the mathematical modelling of a tank process is obtained. Dynamic Matrix Control (DMC) Controller is designed using the mathematical model to control the tank system. The performance of the controller can be analyzedthrough extensive simulation studies.