Automatic generation control of a multi area system using ant lion optimizer algorithm based PID plus second order derivative controller
Abstract This article presents the automatic generation control of an unequal three area thermal system. Single stage reheat turbines and generation rate constraints of 3%/min are considered in each control area. Controllers such as Integral (I) Proportional Integral (PI) Proportional Integral Derivative (PID) and Proportional Integral Derivative Plus Second Order Derivative (PID DD) are treated as secondary controllers separately. A nature inspired optimization technique called Ant Lion Optimizer (ALO) algorithm is used for simultaneous optimization of the controller gains. Comparison of dynamic responses of frequencies and tie line powers corresponding to ALO optimized I, PI, PID and PID DD controller reveal the better performance of PID DD controller in terms of lesser settling time, peak overshoots as well as reduced oscillations. Robustness of the optimum gains of best controller obtained at nominal conditions is evaluated using sensitivity analysis. Analysis exposed that the optimum PID DD controller gains obtained at nominal are robust and not necessary to reset again for changes in loading, parameter like inertia constant H size and position of disturbance. Furthermore, the performance of PID DD controller is found better as compared to PID controller against random loading pattern condition.