Experimental determination of the MHD-EMP effects on power distribution transformers

Conference · Tue Jan 01 00:00:00 EST 1991

OSTI ID:6364419

McConnell, B W; Barnes, P R ^[1]; Tesche, F M ^[2]

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1. Oak Ridge National Lab., TN (United States)
2. Tesche (F.M.), Dallas, TX (United States)

It is a well-established fact that geomagnetic storms influence electrical power transmission and distribution systems. Previous cases of such storms in the northern latitudes have resulted in occasional power disruptions, and in some cases, damage to transformers. These effects are caused by a time variation of the earth's magnetic field creating an induced electric field along the surface of the earth. This E-field acts as a voltage source along long power transmission or distribution lines, and if the line is connected to the earth at both ends, a quasi-dc current can flow. This current can cause unwanted saturation in the magnetic cores of transformers in the power system, and this, in turn produces harmonic distortion and transformer heating. This can lead to system upset (shutdown) and possibly transformer burn-out. The detonation of a high altitude nuclear explosion is also known to affect the magnetosphere, producing late-time variations of the earth's magnetic field for several hundreds of seconds. Known as the magnetohydrodynamic electromagnetic pulse (MHD-EMP), or E{sub 3}, this environment is of particular concern to electrical power systems in the event of a nuclear attack. Although the MHD-EMP induced currents can be significantly larger in magnitude, they last for a shorter period of time than do those from a geomagnetic storm. The effect of this environment compounds the adverse effects of the early-time high altitude EMP (HEMP) environment, posing a potentially serious threat to the electrical system. The present paper documents an experimental program designed to better understand the behavior of distribution-class transformers subjected to quasi-dc current excitation. Given the knowledge of the MHD-EMP-induced current flowing in a long power line, and the transformer response characteristics obtained in this program, it will be possible to make more accurate assessments of the behavior of the overall power system to EMP. 7 refs., 5 figs.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOD; Department of Defense, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6364419
• Report Number(s): CONF-920223-3; ON: DE92003556
• Resource Relation: Conference: 1992 hardened electronics and radiation technology (HEART) conference, Albuquerque, NM (United States), 24-28 Feb 1992
• Country of Publication: United States
• Language: English

Related Subjects

24 POWER TRANSMISSION AND DISTRIBUTION
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
ELECTROMAGNETIC PULSES
TRANSFORMERS
BLAST EFFECTS
ELECTRICAL TESTING
ELECTRIC CURRENTS
ELECTRICAL FAULTS
NUCLEAR EXPLOSIONS
POWER DISTRIBUTION SYSTEMS
POWER TRANSMISSION LINES
CURRENTS
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
EQUIPMENT
EXPLOSIONS
MATERIALS TESTING
NONDESTRUCTIVE TESTING
PULSES
RADIATIONS
TESTING
240200* - Power System Networks
Transmission & Distribution- (1990-)
240400 - Power Transmission & Distribution- Health & Safety- (1990-)
450200 - Military Technology
Weaponry
& National Defense- Nuclear Explosions & Explosives