| dc.description.abstract | In the processing industry, controllers play a crucial role in keeping our plants running—virtually everything from simply filling up a storage tank to complex separation processes, and to chemical reactors. There are some important issues when we design a control system. In the first place, we need to identify the role of various variables. We need to determine what we need to control, what we need to manipulate, what are the sources of disturbances, and so forth. However, chemical processes are highly non-linear in nature, especially when they have multiple inputs – multiple outputs (MIMO) variables with complex interactions. Evaporators usually operate before a major drying process, which require more energy and is difficult to control. It is therefore important to achieve good control in the evaporation stage so that the drying process is operating with steady inputs. In this paper three of main evaporated process variables such as Liquid level in separator, operation pressure, and the product concentration are first controlled using PI controller in the presence of a variables step changes and a load disturbance. Advanced controllers such as model predictive control that is used for a wide range of application in the process industry. The potential utilization of such advanced predictive controllers is to design control systems that give effective control in this multivariable environment. Model predictive control is applied to the evaporated process with same mentioned conditions for variable step changes and load applied in case of PI controller. The objective of this paper is to present and illustrates in a comparatively study to the results obtained by PI controller, the use of MPC in providing an effective control for a MIMO evaporator plant in the presence of step and load disturbances change. The sum of the integral of absolute error (IAE) is used as a criterion for evaluating the controller’s performance. | en_US |
