Figure 25. SC Stator Current on 100kM Overhead Line energization for a SCIG (left) and DFIG (right) based hybrid system.
As previously explained, the missing zero phenomenon was more significant for the DFIG based system as compared to the SCIG system as a result of presence of capacitor banks making the system more capacitive for the SCIG based hybrid system.
3.6. Cold Load Pickup-Motor Energization
Still on the assumption that there is a non-black start unit located 50km from the windfarm, and with the knowledge of maximum reactive power pickup of around 2MVAr, a 3MVA motor was assumed to be the largest motor in the plant. Fig. 26 shows the results obtained for both the SCIG and DFIG based system.