The activation of Crowbar protection and its action time both have impacts on the short-circuit current characteristics of doubly fed induction generator（DFIG）.Nowadays，most studies assume the instantaneous activation of Crowbar protection after the occurrence of voltage sag.However，in practice，the Crowbar protection acts with different time delay depending on the severity of the voltage sag，which complicates the precise calculation of the short-circuit current.Aiming at this practical problem，this paper takes asymmetrical fault occurred at the stator terminal as an example.The fault current is divided into positive and negative sequence component in the forward and reverse synchronous rotating reference frame respectively，and the fault process is divided into two stages according to the Crowbar insertion moment.The formula of the fault currents during the fault process is derived in detail，and compared with the standard DFIG simulation model provided by MATLAB/Simulink.The comparison results validate the proposed formula and the effect of insertion time on DFIG short-circuit current characteristics.