TY - JOUR
T1 - Transformer neutral blocking device to prevent the flow of geomagnetically induced currents in power systems
AU - Porter, Joseph W.
AU - Kappenman, John G.
AU - Norr, Scott R.
AU - Simo, Stephen
PY - 1993/12/1
Y1 - 1993/12/1
N2 - Geomagnetically-induced currents (GIC), which cause detrimental effects to electrical equipment and power system operation, enter power systems through grounded neutral leads of wye-connected transformers. The Electric Power Research Institute (EPRI) has sponsored research into strategies which mitigate the effects of geomagnetic disturbances. One such strategy involves the use of a Neutral Blocking/Bypass Device (NB/BD) which can be inserted in power transformer neutral-ground connections to block the flow of GIC while maintaining a low-impedance AC grounding path. The device consists of distribution capacitors which provide the blocking function for the quasi-dc geomagnetically-induced currents. The capacitors are rapidly bypassed by a combination of a sparkgap and circuit breaker to solidly ground the neutral during power system disturbances. The sparkgap provides the fast operating response speed, while the circuit breaker provides a secure metallic bypass of the capacitor. In both simulation, and in rigorous field test, the bypass operation will occur rapidly (less than 1 msec) and will both prevent ferroresonant over-voltages and preserve proper protective device operation.
AB - Geomagnetically-induced currents (GIC), which cause detrimental effects to electrical equipment and power system operation, enter power systems through grounded neutral leads of wye-connected transformers. The Electric Power Research Institute (EPRI) has sponsored research into strategies which mitigate the effects of geomagnetic disturbances. One such strategy involves the use of a Neutral Blocking/Bypass Device (NB/BD) which can be inserted in power transformer neutral-ground connections to block the flow of GIC while maintaining a low-impedance AC grounding path. The device consists of distribution capacitors which provide the blocking function for the quasi-dc geomagnetically-induced currents. The capacitors are rapidly bypassed by a combination of a sparkgap and circuit breaker to solidly ground the neutral during power system disturbances. The sparkgap provides the fast operating response speed, while the circuit breaker provides a secure metallic bypass of the capacitor. In both simulation, and in rigorous field test, the bypass operation will occur rapidly (less than 1 msec) and will both prevent ferroresonant over-voltages and preserve proper protective device operation.
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M3 - Conference article
AN - SCOPUS:0027879321
VL - 55
SP - 1640
EP - 1645
JO - Proceedings of the American Power Conference
JF - Proceedings of the American Power Conference
SN - 0097-2126
IS - pt 2
T2 - Proceedings of the 55th Annual Meeting of the American Power Conference. Part 1 (of 2)
Y2 - 1 April 1993 through 1 April 1993
ER -