2DOF-PID Controller-Based Load Frequency Control of Linear/Nonlinear Unified Power System

摘要

This paper describes about the Load Frequency Control (LFC) of an interconnected linear/nonlinear power system having two degree freedom of PID controller (2DOF-PID). The reheat thermal applied on a two-area system is considered for frequency control analysis by applying an abrupt load perturbation of 0.1 pu in area 1. Two systems are scrutinized for studying the load frequency control namely a linear system and a nonlinear system. The nonlinearities of the system are included by implementing governor with dead band (GDB) in each of the areas. The parameters of 2DOF-PID controllers are tuned on basis of Cuckoo Search Algorithm (CSA) considering time domain based fitness function, i.e., ITAE (Integral Time Absolute Error). For both types of system the dominance of 2DOF-PID controller is proved over conventional PID controller in terms of responses like minimum undershoot, settling time and peak overshoot. The supremacy of the recommended methodology is also established over some pre-published results.