Three-phase short circuit analysis of DFIG-based wind generation and the crowbar biggest resistance setting

The short-circuit current contribution of wind turbines has not received much attention so far. This paper establishes the doubly fed induction generator mathematical model and carried on corresponding short circuit analysis. Regarding the sudden short circuit process as a superimpose of steady state operation and transient state operation provoked by reverse voltage, stator three-phase short circuit current expression is obtained by carrying on the Laplace transformation and the inverse transformation to the state space equation. And the expression is confirmed by simulation. In addition, the character and attenuation rule of stator short circuit current component are analyzed, and maximum resistance of short circuit protective device is set.