Fuzzy based STATCOM for Reactive Power Compensation in Grid Connected Wind Farm

In modern electrical distribution systems harmonic distortions are created from a number of sources such as variable frequency drives, lighting, computers and nonlinear loads. Such harmonic distortions produce a variety of undesirable side effects ranging from poor power factor, motor failure to overloading of transformers and conductors. Now a days increasing number of renewable energy systems such as solar and wind turbine generators are connected to the existing power system in order to reduce the negative environmental impact of fossil fuel based conventional electric power generation schemes. But power quality of an electric grid is affected by the penetration of intermittent wind power into it. This paper analyses the harmonic distortion problem, which arises due to the integration of fixed speed induction generator based wind energy conversion system with electric grid which is already incorporated with nonlinear load. In the proposed scheme STATic COMpensator (STATCOM) is connected at Point of Common Coupling (PCC) to provide dynamic reactive power compensation required by grid connected wind farm for maintaining voltage within prescribed limits as well as harmonic mitigation endow with grid codes. Mamdani based fuzzy logic controller has been designed for controlling STATCOM. The viability and effectiveness of the proposed fuzzy control strategy in steady state is verified and proved by creating a simulation model of a small grid connected wind farm with nonlinear load in MATLAB/SIMULINK. It is clearly presented that STATCOM with FLC reduces Total Harmonic Distortion (THD) of source current in power system connected with fixed speed wind farm and nonlinear load.