Behavior of doubly-fed induction generator during symmetrical voltage dips — Experimental results

Wind energy conversion systems using the doubly-fed induction generator (DFIG) are the most commercialized topology worldwide, because this technology uses converters dimensioned for ±30% of the system rated power, thus reducing the equipment cost. The direct connection of the DFIG stator to the electrical system increases its sensitivity to grid disturbances. In this context, this paper analyzes the DFIG behavior during balanced voltage sags using the machine classical model for the theoretical development and analyzing experimental results of a 2.2 kW test bench equipped with a crowbar device. The obtained results are useful in the development of strategies to improve the DFIG supportability during grid disturbances.