The large-scale grid-connection of doubly fed induction generator（DFIG）has changed the fault characteristics of the power grid

and then affected the operation characteristic assessment of the relay protection devices. Therefore

it is very important to study the lower voltage ride through（LVRT）characteristics of DFIG. However

the current researches haven't fully considered the influences of the latest wind turbine grid-connection requirements

the actual LVRT control strategy and the grid-side converter（GSC）on the steady-state short-circuit current of DFIG. In this paper

the steady-state models of stator and GSC during LVRT period is set up respectively on the basis of the LVRT strategy of DFIG of mainstream factories and the latest wind turbine grid-connection requirements in China

and a practical calculation method for the steady-state short-circuit current of DFIG is proposed. Furthermore

a semi-physical simulation platform including actual controller of DFIG is set up on RTLAB further. It is verified that the calculation error of the effective value of short-circuit current by the practical calculation method is less than 3%

and the calculation error of the short-circuit current phase angle is less than 2.5%. The research results in this paper are of great significance to the relay protection setting of DFIG access system.