The connection to the grid of wind turbines

With a view to the integration in national power system of new power plants based on renewable energy sources, such as wind energy, this paper presents the technical requirements related to the connection of the wind power plants to the main grid. Grid connected wind turbines may cause power quality problems, such as voltage variation and flicker, and therefore, the connection of wind farms requires new connecting rules to avoid negative effects on the existing electrical system. System operators usually issue these rules in the form of grid codes. The paper should be helpful to facilitate the orientation in finding of adequate type of wind turbines that can be installed in the intended sites, dependent on specific conditions.