Effects of geomagnetic disturbances on electric power transmission systems

Technical Report · Thu Aug 01 04:00:00 EDT 1991

OSTI ID:5340068

Meliopoulos, A P.S.; Glytsis, E N ^[1]; Cokkinides, G J ^[2]

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1. Georgia Inst. of Tech., Atlanta, GA (United States). Electric Power Lab.
2. South Carolina Univ., Columbia, SC (United States). Dept. of Electrical Engineering

A comparative study of the effects of solar storm geomagnetically induced current (SS-GIC) and nuclear detonation induced currents (MHD-EMP-GIC) on the power system is presented. The earth surface electric field of the MHD electromagnetic pulse is given to be on the order of 100 V/km, with a duration up to several minutes; and the electric field of the solar storms is given to be on the order of 10 V/km, and lasts from several minutes to one hour. Both phenomena cause flow of almost direct current in the windings of power transformers through the grounding system. For lone transmission lines, i.e. 300 miles or longer, this DC current offsets the 60 Hz AC and may saturate transformer cores, with secondary results such as high magnetization currents, increased harmonics, and concomitant effect on power system operation. The level of the transformer core saturation depends on the time constant of the saturation process, and on the duration and magnitude of the direct current through the transformer windings, but the degree of transformer saturation is comparable. Thus, the effects on system voltage could be expected to be about the same. Furthermore, although the solar storm electric field is much lower than MHD-EMP, the solar storm effects on the power system, from the thermal stress point of view, are greater due to their much longer duration. A technique for the computation of the induced and/or transferred voltages and currents to an electric power system form geomagnetic disturbances is presented. Models of transmission lines which explicitly represent grounding, earth potential, and frequency dependent phenomena, and power transformers which explicitly represent nonlinear magnetization characteristics, are utilized. A parametric analysis of saturation time constants is performed and the effects of MHD-EMP and SS-GIC are compared. 36 refs., 14 figs., 8 tabs.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); Georgia Inst. of Tech., Atlanta, GA (United States). Electric Power Lab.; South Carolina Univ., Columbia, SC (United States). Dept. of Electrical Engineering
• Sponsoring Organization: EPRI; Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 5340068
• Report Number(s): EPRI-EL-7333
• Country of Publication: United States
• Language: English

Related Subjects

24 POWER TRANSMISSION AND DISTRIBUTION
240200* -- Power System Networks
Transmission & Distribution-- (1990-)
640201 -- Atmospheric Physics-- Auroral
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71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BLACKOUTS
COUPLINGS
CURRENTS
DETONATIONS
DISTURBANCES
DOCUMENT TYPES
ELECTRIC CURRENTS
ELECTRIC FIELDS
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC PULSES
ELECTROMAGNETIC RADIATION
ENERGY SYSTEMS
EQUIPMENT
EXPLOSIONS
GEOMAGNETIC FIELD
MAGNETIC FIELDS
MAGNETIC STORMS
NUCLEAR EXPLOSIONS
POWER DISTRIBUTION SYSTEMS
POWER SYSTEMS
PROGRESS REPORT
PULSES
RADIATIONS
SOLAR ACTIVITY
SOLAR FLARES
TRANSFORMERS