Relation of geomagnetically induced currents and local geomagnetic variations

Author

Viljanen, Ari

Author_Institution

Div. of Geophys. Res., Finnish Meteorol. Inst., Helsinki, Finland

Volume

13

Issue

4

fYear

1998

fDate

10/1/1998 12:00:00 AM

Firstpage

1285

Lastpage

1290

Abstract

Geomagnetically induced currents (GICs) were recorded in June 1991 to May 1992 in a 400 kV transmission line in southern Finland. Geomagnetic field variations were simultaneously measured at the nearby Nurmijarvi Geophysical Observatory. Two models are presented here to calculate GICs from the time derivative of the magnetic field. A plane wave model with a homogeneous earth is applied by letting the Earth´s conductivity be a fitting parameter. Another approach derives experimental impulse responses between GIC and time derivatives. Both methods yield approximately accuracy. When GICs larger than 10 A, 20 A and 30 A are considered the average misfits are ca. 40%, 30%, and 20%, respectively

Keywords

electric current measurement; electrical faults; geomagnetic variations; power system measurement; power transmission lines; transmission line theory; 400 kV; Finland; experimental impulse responses; fitting parameter; geomagnetic field variations; geomagnetically induced currents; homogeneous earth; magnetic field time derivative; plane wave model; transmission line; Conductivity; Earth; Geomagnetism; Geophysical measurements; Magnetic field measurement; Observatories; Power transmission lines; Storms; Transmission line measurements; Transmission line theory;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.714497

Filename

714497