Multivariable H-Infinity model matching control of a heat exchanger network (HEN) with bypasses

A countless of different multivariable control techniques, ranging from decentralized PID to predictive controls, are presented in several literatures and applied to chemical plants. This work intends to present a study developed using a control solution based on optimal control, applied on a heat exchanger network (HEN) with bypasses. The HEN is frequently used in chemical processes to promote energy integration, reducing the utility consumption as its main objective. A H-Infinity model matching control was developed successfully to the network by using time domain specification instead of the traditional frequency domain specification. The results of the simulations have demonstrated that the proposed optimal control leaded to a reasonable control performance, i.e., process variables became almost totally decoupled, null offset, and the output responses presented a small time constant.