Automatic Generation Control Using LQR based PI Controller for Multi Area Interconnected Power System

The continuous time Linear Quadratic Regulator (LQR) theory has been implemented in the present work for the design of optimal Proportional Integral(PI) controller for the frequency response enhancement of multi area interconnected power system . The PI controller gains as proportional gain (Kp) and integral gain (Ki) are formulated as the optimal state-feedback gains, corresponding to the standard quadratic cost function known as integral of time multiplied squared error (ITSE).The two area network comprising of thermal power systems is considered without the reheat and generation rate constraint (GRC). The automatic generation control has been developed for two area thermal network using LQR based PI controller. In the present work firstly the block diagram of the system is designed. Then states of the system are identified which help to develop the state apace model of the system. The proposed model has nine states of the system for which the state feedback is given to LQR for keeping the Performance Index (PI) to minimum. The system state equation and output equation have been formulated with state matrix A, Input matrix B and Output matrix C. These matrices are developed on the basis of system parameters. The weighing matrices Q and R of LQ regulator are optimally designed to keep the frequency deviation with load changes within the desired limits. The two control signals are thus developed by LQ regulator which are fed one to each area for frequency response enhancement..The proposed load frequency control of two area electric power system has been developed by using MATLAB/SIMULINK. The thermal systems of two area network are Naresh Kumari & A.N. Jha 15