Frequency control of multi-area power system network using PSO based LQR

Abstract

The mathematical modeling of two area network with interconnected thermal power systems has been done on the state space and an optimal control system technique known as Linear Quadratic Regulator (LQR) along with proportional integral (PI) controller is designed for the frequency response enhancement of the system in this paper. The PI controller gains are taken as the optimal state-feedback gains along with other state variables of the system for automatic generation control(AGC). The reheat turbine for thermal areas have been considered for the system. When the load on the system changes the variation in the frequency should be minimum for a system with properly designed automatic generation control. To enhance the frequency response against the load changes, the optimal controller known as Linear Quadratic Regulator (LQR) is tuned by powerful computationally intelligent technique Particle Swarm Optimization (PSO). In the present work first the block diagram of the two area interconnected thermal power system is designed. Then the state equations for the power system are obtained for the different states in the block diagram to develop the state space model. The proposed PSO based LQR technique for automatic load frequency control of two area thermal power system has been developed by using MATLAB/SIMULINK.