Using a finite element (FE) model of the electrical machine in a grid solver enables us to take the machine nonlinearities into account with great precision in the simulation of a complete system. Three methods are usually used for linking the grid and FE solver: direct coupling, lumped components, and current or voltage output approach. In this article, the coupling is treated as the resolution of a nonlinear equation system that is solved with the Newton method. The proposed linking scheme has been used to simulate a two phase short circuit on a hydrogenerator. Its results have been validated by running the same simulation with commercially available software.