Load frequency control in an AC microgrid

Abstract

In the present scenario, due to the staggering increase in demand for electrical energy, system stability becomes an important concern. When electrical power demand increases, it creates unnecessary frequency oscillation and voltage oscillation in the power system, and hence a lot of pressure are put on it. The increase in the complexity of the power system and connection of various sources, renewable energy can be considered as one of the best alternative source. In our complex grid systems, now a days very much increase in the number of micro-grids (MGs), the existence of a sudden and random load perturbation, uncertainty in the parameter and due to variation in the structure, the operating frequency is not the same as the required frequency. For the purpose of reduction in the frequency deviation and maintaining balance between power generated and the load, our grid system requires an intelligent, sophisticated and easily controllable at optimized point. In this age obscure controllers are not efficient enough to facilitate a wide range of operation. For this purpose, this thesis presents an integration of both fuzzy logic and conventional PI controller with various techniques for optimal tuning of our controllers in the AC micro grid systems. The tuning of PI controller and its control parameters are obtained from Ziegler-Nichols tuning method to optimized the parameter. The systems including the transfer function models are designed and simulated in a user friendly and most reliable MATLAB/Simulink environment.