Analysis of Load Frequency Control in a restructured multi-area power system with the Kalman filter and the LQR controller

The performance of power systems in restructured environments has become increasingly more complex due to the technical limitations and traditional requirements. To this end, electrical power systems act independently in the generation, transmission and distribution of electricity, leading to restructuring and deregulation. On the one hand, technical requirements for transmission lines and renewable energies will contribute to HVDC transmission. On the other hand, one of the main goals of the Automatic Generation Control (AGC) is to manage Load Frequency Control (LFC) in a multi-area power system. In order to examine the internal and intrinsic stability, the Linear Quadratic Regulator (LQR) control method was used but since neither all the state variables were available nor their measurements were noise-free, the LQR controller was used with the Kalman filter (KF) for the real-time control for solving the LFC problem. Finally in the section on the simulation, a comparison was made using MATLAB, between two multi-area power systems consisting of thermal and hydroelectric generation units, one of which with the HVDC transmission lines and the other one without them, in terms of frequency stability. Moreover, the simulation results indicated that the introduced control method led to the improved LFC performance in a multi-area power system with HVDC transmission links.