Abstract: The characteristics of short-circuit current contributed by new energy is significantly different from that of traditional induction machine. With the centralized access of high proportion renewable energy, its contribution to the short-circuit current has become the focus of attention. In this paper, the mechanism of short-circuit current contributed by doubly-fed induction generator (DFIG) was studied. The electromagnetic transient model of vector control method of DFIG was established. The expressions of rotor current and stator current of DFIG were derived for the two control strategies of continuous excitation control of the converter when the voltage was slightly dropped and Crowbar control strategy when the voltage was seriously dropped. Combined with the change of the electrical boundary conditions after fault, the control strategy of DFIG was switched from continuous excitation control strategy of the converter to Crowbar control strategy. An analytical formula considering the short-circuit current in the switching process of the control strategy was derived and a calculation method of short-circuit current considering the control switching process was proposed. The comparison of the simulation results of PSCAD verifies the correctness of the theoretical analysis and proves the effect of the control strategy switching process on the short-circuit current after the fault. The proposed method advanced the mechanism research of the contribution of new energy to the short-circuit current, which is beneficial to the improvement of calculation accuracy.