Influence of stator turn-to-turn short-circuit on magnetic field of DFIG

Doubly fed induction generator (DFIG) are mainly used in wind power system where its reliability is important requirement. In DFIG, stator internal turn-to-turn short-circuit is a common fault. Analysis by Electro-Magnetic Field (EMF) modeling is very promising in detecting stator inter-turn faults in DFIG. Hence, in this paper an in-depth investigation is conducted by electromagnetic performance of a DFIG with stator turn-to-turn short-circuit. The finite element method (FEM) is used to model EMF of DFIG under various stator turn-to-turn short-circuit, this model takes into account teeth and slots effect of stator and rotor, saturation of core. It is easy to simulate different positions and degree stator turn-to-turn short-circuit conditions in DFIG by change the particular parameters. The harmonic components of air-gap flux density are studied. The model and simulated results are validated by test data of a DFIG. The approach presented in this paper will provide the protection basis for the DFIGs with stator inter-turn short circuit fault.