Investigation of the impact of speed-ripple and inertia on the steady-state current spectrum of a DFIG with unbalanced rotor

This paper investigates the influence of speed ripple and effective rotational inertia on the stator current harmonic content of a DFIG operating with a rotor electrical unbalance. For this purpose a time-stepped numeric DFIG model is employed. A model study is performed for a range of operating scenarios of interest. The effect of different types of rotor unbalance (supply/windings) on the stator current spectrum is also examined.