Analysis of doubly fed induction generator wind turbine system during one phase-to-ground fault

This paper presents detailed analysis of doubly fed induction generator (DFIG) wind turbine electrical components during normal and unbalanced fault condition. Wind turbine components are individually modeled and then combined in a simulation process which is called coupled simulation. The coupled simulation results show that grid frequency oscillation occurs on q and d axis currents under one phase-ground fault condition. Experimental study has been done to show the effects of fault on rotor currents. Same behavior is also found in experimental rotor currents. Additionally experimental study shows that rotor currents are very sensitive to the grid fault voltage level.