With the increase of DFIG capacity and the influence that the wind turbine to power grid relay protection gradually increased, the research which applies to relay protection of DFIG setting short-circuit current calculation method is particularly important. In order to solve this problem and consider the practicability of setting calculation of relay protection, this paper establishes a protection setting calculation of DFIG equivalent model for the relay. Through the derivation of the doubly fed wind turbine basic formula, the simplified equivalent circuit of DFIG is got. By studying the simplified equivalent circuit and the transient process of DFIG with short circuit fault, the expression of equivalent electromotive force is derived, and the formula of short circuit current of DFIG is derived. Finally, the accuracy of equivalent circuit and short-circuit current calculation formula is verified by simulation. It provides a new equivalent model for relay protection calculation of DFIG. This work is supported by National High-tech R & D Program of China (863 Program) (No. 2015AA050101).