Nordic GIC Network

Disturbances 6-7 April 2000

Lund Space Weather Center

Reports regarding the April 6-7, 2000, geomagnetic substorm
Svenska Kraftnät, Lars Wallin, reported:

No disturbances related to the high GIC values of April 6 where noticed in the Swedish transmission network (stamnätet).

Sydkraft did not notice any disturbances, but a tap-changer operated during the disturbance, due to a drop in voltage in a substation in the transmission network. An MVAr increse was noticed at a few substations. Sydkraft registered a GIC of a few hundred Amperes in a power plant. This caused no disturbance.
Eltra, Hans Abildgaard, reported:

In the mentioned period no forced outages have occured in the transmission network (150-400 kV) in the western part of Denmark.

FINGRID OYJ, Matti Lahtinen, reported:

Fingrid have recorded the incident at Rauma and Yllikkälä.

In Rauma the maximum GIC was recorded 6.4. 2000 at 23:21:40 UT, about 17 A.

In Yllikkälä the maximum GIC was recorded 6.4. 2000 at 23:23:30 UT, about 9 A.

No disturbances or malfunctions has been reported in Finnish transmission grid.

FMI/Geophysical Research Division, Antti Pulkkinen, reported (concerning GASUM):

Just as the Finnish power system, the Finnish pipeline did not have any operation failures because of the Apr 6-7 magnetic storm.

However, both large GIC and pipe-soil-voltage variations were measured. The maximum GIC was approx. 23 amps (for data-plot see which is the largest value of the whole GIC measurement period (started in Nov 1998).

A report page like this, but with the addition of data from the Sun to the Earth is available here.


Nordic GIC Network