Linear Quadratic Regulator Technique for Optimal Load Frequency Controller Design of Interconnected Linear Power Systems

Abstract

Frequency is a significant criterion for the reliability of large-scale multi-area power systems. Active power balance and steady frequency are necessary to provide stability for the interconnected power system. It is interesting to note that frequency relies on active power balance. Therefore, in order to enhance the reliability of the power networks, a load frequency control (LFC) system must be designed to control the power generation and the active power at the tie lines. In this paper, a subset of classical control theory regarded as an optimal control concept was utilized to design controls for the complex power systems by minimizing a performance index based on the system variables. The goal of optimal regulator design is to determine the optimal control law of a two-area power system that can shift the system from an initial state to the final state in such a way that a given performance index is significantly mitigated. The performance indicator is chosen to offer the best possible trade-off between performance and control costs. In the optimal control method used in this paper, a quadratic performance index is used, and it is based on minimum energy criteria and minimal error. The MATLAB / Simulink environment was used to simulate the overall system structure.