Optimal Controller for Single Area Load Frequency Control via LQR and Legendre Wavelet Function

Hatem Elaydi^1, and Mohammed Wadi²

¹Electrical Engineering Department, Islamic University of Gaza, Gaza, Palestine

²Electrical Engineering Department, Yildiz Technical University, Istanbul, Turkey

Cite this paper:
Hatem Elaydi and Mohammed Wadi. Optimal Controller for Single Area Load Frequency Control via LQR and Legendre Wavelet Function. Journal of Automation and Control. 2015; 3(2):43-47. doi: 10.12691/automation-3-2-2

Abstract

Load frequency control (LFC) is an important tool to insure the stability and reliability of power systems. Nowadays power demand is increasing continuously and the biggest challenge is to provide uninterrupted electrical energy to consumers under changing conditions. For satisfactory operation, the frequency of power system should be kept near constant value or within standard value; in addition to that an uninterrupted power should continue to flow despite the variations of load in different areas. Many techniques have been proposed to guarantee the uninterrupted flow of power and the constant value of frequency and to overcome any deviations. In this study, optimal control based on Legendre wavelet function and linear quadratic regulator (LQR) techniques are applied to single area power system in order to approximate the gain of controller to overcome the fluctuations of frequency in electrical power systems. This paper models a single area power system with optimal control strategies based on LQR and Legendre wavelet transform and presents simulation results using Simulink/MATLAB. The paper also compares the performance of the LQR and Legendre wavelet transform controllers. A numerical example is solved in order to demonstrate the effectiveness of the proposed technique.

Keywords:
Load Frequency Control (LFC) Automatic Generation Control (AGC) Legendre Wavelet Function Linear Quadratic Regulator (LQR) Single Area Power System

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