Measurement and simulation of power quality issues in grid connected wind farms

Wind energy sources are crucial if they are to be effectively exploited in the grid network. But, the grid connection brings the problems of power evacuation, power quality issues and unwanted tripping of generators. The paper presents the issues in the power quality of a variable speed wind farm synchronous generator located at Tamilnadu (India). According to IEC 61,400-21, the power quality events such as voltage fluctuation, harmonics and flicker are measured by power quality analysers connected at the selected locations in the wind farm. A wind turbine model and its control strategy are developed using the DIgSILENT simulation software. The control schemes for the generator side and the grid side converters are implemented to assure the power quality problems. With the simulation model, various circumstances and their effect on the performance of the wind farm are analysed. The results of the simulation are related to the recorded waveform to validate the model of the wind farm. This study will be useful for the turbine operators and manufacturers to assess the causes and severity of power quality issues well in advance to implement the necessary remedial measures.