LQ control of heat exchanger-Design and simulation

Heat exchangers are devices whose primary responsibility is the transfer (exchange) of heat, typically from one fluid to another. However, they are not only used in heating applications, such as space heaters, but are also used in cooling applications, such as refrigerators and air conditioners. Heat exchange processes often contain time-delay. This paper deals with design of universal and robust digital control algorithms for control of great deal of processes with time-delay. These algorithms are realized by the digital Smith Predictor (SP) based on polynomial approach-by minimization of the Linear Quadratic (LQ) criterion. For a minimization of the LQ criterion is used spectral factorization with application of the MATLAB polynomial Toolbox. The designed polynomial digital Smith Predictors were verified in simulation conditions. Simulation model for a verification of the designed control algorithms was realized using experimental measured data on the laboratory heat exchanger. The program system MATLAB/SIMULINK was used for simulation of the designed algorithms. © ECMS Valeri M. Mladenov, Petia Georgieva, Grisha Spasov, Galidiya Petrova (Editors)