Internal model control for single tubular heat exchanger system

Internal model control (IMC) was implemented for the temperature control of a single tubular heat exchanger system. The experimental heat exchanger system was a very simple structure, however, the characteristics were regarded as a distributed parameter system. Since IMC used the system model, it was necessary to identify the parameters precisely. The step response and the usual frequency response method and least square method were used for 1st order plus time delay, and 2nd order system and for fitting the coefficient of the partial differential equation, respectively. In this laboratory experiment, it was clear that: (1) since the IMC structure includes a PI controller, the performance of the IMC was superior to PI control; (2) the only tuning filtering parameter of the IMC controller affected the sensitivity and robustness; and (3) since IMC controller was constructed from the system model, it is very important to set up the plant model and identifications