Power System Fault Ride through Capabilities of Induction Generator Based Wind Turbines

Abstract

Until recently it has been accepted that induction generator based wind turbines are disconnected from the power system in the event of a network disturbance. However, the increasing trend of connecting high penetrations of wind farms to transmission networks has resulted in the transmission system operators revising their grid codes for the connection of large MW capacity wind farms. These documents now require wind turbines to remain connected for a specified voltage disturbance on the network. Much of the wind generation plant being developed will use either fixed speed induction generator (FSIG) or doubly fed induction generator (DFIG) based wind turbines. The ability of induction generator based wind turbines to remain connected through power system disturbances is discussed. A control loop for a ‘fast pitching’ blade angle control strategy to provide a power system fault ride-through capability for induction generator based wind turbines is also described. A case study of a FSIG wind turbine with the ‘fast pitching’ initiating logic and control scheme is investigated.