Multi-objective optimal tuning of two degrees of freedom PID controllers using the ENNC method

In this paper the Enhanced Normalized Normal Constrained method is applied to find the optimal tuning of second order PID controllers. This tuning takes into account both the servo and regulatory modes simultaneously, as well as a closed loop robustness criterion. The methodology is successfully applied to a high order linear plant and to a non linear continuous stirred tank reactor model, showing the effectiveness of the optimization methodology to solve control related problems. Also, the method is applied to a benchmark control system that takes into account three different sources of disturbances.