Comparison of performances of several Cuckoo search algorithm based 2DOF controllers in AGC of multi-area thermal system

Abstract

This paper presents the automatic generation control (AGC) of an unequal three area thermal system with single reheat turbine and generation rate constraints of 3%/min in each area. A two degree of freedom (2DOF) controller called 2DOF – integral plus double derivative (2DOF – IDD) is proposed for the first time in AGC as secondary controller. Secondary controller gains and other parameters are simultaneously optimized using a more recent and powerful evolutionary computational technique called Cuckoo search algorithm (CS). The system dynamic responses obtained with 2DOF – IDD controller are compared with that obtained with other 2DOF controllers such as 2DOF – Proportional-Integral (2DOF – PI), 2DOF Proportional – Integral-Derivative (2DOF – PID). Investigations reveals that 2DOF – PI, and 2DOF – PID provide more or less same response where as 2DOF – IDD controller provides much better response than the others. Sensitivity analysis reveals that the CS optimized 2DOF – IDD controller parameters obtained at nominal condition of loading and nominal size of step load perturbation (SLP) are robust and need not be reset with wide changes in system loading and (SLP).