Finite element analysis of winding fault effects in a wound-rotor induction machine with experimental validation

Effective condition monitoring of remote wind turbine power plant induction generators is significantly gaining importance in modern wind industry. This paper uses a finite element time stepping transient model to investigate the influence of winding faults on the air-gap field distribution of a wound-rotor induction generator. The analysis shows that winding faults cause a severe air-gap field distortion, giving rise to field harmonic orders that would not otherwise be present in the air-gap, and links these to observed winding fault specific changes in the predicted and measured machine current spectrum.