New England Electric's 39 years of experience with resonant neutral grounding of unit-connected generators

Abstract

Since 1951 all unit connected generators of the New England Electric System Companies have been grounded using ground fault neutralizers (GFNs). This grounding method permits protection against phase-to-ground faults on the generator bus that is more sensitive than with resistor grounded units. In addition, the fault current is limited to such a low value that the possibility of stator iron burning is practically eliminated. Also, because of the limited fault current, overvoltage due to arcing is not possible. These advantages of ground-fault neutralizer generator protection are illustrated through discussion of actual operating experience and by calculations for a typical generator.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>