Reactance Zero-phase sequence

X2 and afo are negative and zero phase sequence reactances of the generator respectively, in ii/phase. 

The naturai zero phase sequence inductive reactance of the grounded neutral may be considered to be too small compared to this and ignored for ease of calculations. Thus the resistance Rq of the grounded neutral circuit may be considered as its impedance, i.e. 

Generators that are solidly grounded have a different grounding practice from others due to their zero phase sequence reactance, which is much less than its positive or negative phase sequence reactances (Section 13.4. ((. i))... 

Zero phase sequence reactance Xg has a value lower than X and is a complex function of the slot pitching of the stator windings and the leakage reactance present in their end windings, see Reference 7, Chapter XII. 

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