IEEE Transactions on Energy Conversion, Vol.21, No.3, 652-662, 2006
Control of a doubly fed induction generator in a wind turbine during grid fault ride-through
This paper analyzes the ability of a doubly fed induction generator (DFIG) in a wind turbine to ride through a grid fault and the limitations to its performance. The fundamental difficulty for the DFIG in ride-through is the electromotive force (EMIT) induced in the machine rotor during the fault, which depends on the dc and negative sequence components in the stator-flux linkage and the rotor speed. The investigation develops a control method to increase the probability of successful grid fault ride-through, given the current and voltage capabilities of the rotor-side converter. A time-domain computer simulation model is developed and laboratory experiments are conducted to verify the model and a control method is proposed. Case studies are then performed on a representatively sized system to define the feasibility regions of successful ride-through for different types of grid faults.
Keywords:current control;doubly fed induction generator (DFIG);flux linkage;grid fault;power converter;safe operating area (SOA);wind energy