DEADBEAT CONTROL OF A CSTR

Abstract

It is known that a first order process with dead time is unstable. Therefore a suitable controller is required to give the system output response within the permissible range. A deadbeat controller gives response that exhibit zero error at all sampling instants after the first instant when subjected to a unit step change in the set point. Based on the literature review, it was observed that there was scarcity of infdrmation on performance of MRDC schemes for system of Chemical Engineering interest. So, it was thought desirable-to investigate the response of deadbeat controller schemes considering a continuous stirred tank reactor as process that corresponds to a system of first order with dead time. It is observed that the MRDC Scheme with ( g = -0.2 and -0.8) are quite robust as they give good response even it the process parameters are poorly known i.e. both the time constant of the process (Tp) and the dead time (Td) are in error 50% of the original estimate, whereas the CDC scheme in such a case is not robust and give poor response.