An aggregate model of PMSG-based, grid connected wind farm: Investigation of LVRT capabilities

Large scale integration of wind power has become one of the most important challenges of wind industry. To increase wind power penetration on power systems, modern wind farms are required to operate like conventional generating unit. They should participate to frequency and voltage control and stay connected to the grid during severe disturbances. In this context, an aggregate model of a grid connected wind farm is developed in this paper. The wind farm includes 25 direct drive wind turbines of 2 MW rating each. The cluster or multi-machine equivalent representation was used to achieve the necessary accuracy under different incoming winds. This model will be used to investigate the behavior of power systems including wind farms and to improve the planning and the exploitation of electricity systems. A hierarchical control approach is developed to manage wind farm active and reactive generation during voltage dips and to investigate its Low Voltage Ride-Through (LVRT) capacity.