COMPARATIVE ANALYSIS OF A SINGLE AREA LOAD FREQUENCY CONTROL USING INTELLIGENT CONTROLLERS

Abstract

Power quality of a system can be improved by keeping the frequency and voltage magnitude within tolerable limits. As the load increases, the system frequency drops and vice versa. This variation in the frequency is undesirable and is taken care by load frequency control. Load frequency control mainly helps to keep the frequency within limits and to give zero steady state error. It is the basis of many advanced concepts of the large scale control of the power system. When dealing with the LFC problem of power systems, unexpected external disturbances, parameter uncertainties and the model uncertainties of the power system pose big challenges for controller design. In this study, Intelligent controllers like Hybrid Neuro-Fuzzy and Fuzzy tuned PID controllers for load frequency control of a single area thermal power system are designed and the results are compared with the conventional PI and PID controllers. Fuzzy logic based intelligent control technique for tuning the conventional controller provides a formal method for implementing the human heuristic knowledge in the form of control rules. The FLC tune the proportional (Kp), integral (Ki) and derivative (Kd) gains of the conventional PID controller depending upon the frequency error (e) and the change in frequency error (ce). The characteristics of a fuzzy system such as robustness and adaptability can be successfully incorporated into the controlling method for better tuning of PID parameters. A Neuro-Fuzzy system is a Fuzzy system that uses a learning algorithm derived from neural network theory to determine its parameters by processing data samples.