Effects of neutral point reactors and series capacitors on geomagnetically induced currents in a high-voltage electric power transmission system
Article first published online: 23 NOV 2011
Copyright 2011 by the American Geophysical Union.
Volume 9, Issue 11, November 2011
How to Cite
2011), Effects of neutral point reactors and series capacitors on geomagnetically induced currents in a high-voltage electric power transmission system, Space Weather, 9, S11005, doi:10.1029/2011SW000715., , and (
- Issue published online: 23 NOV 2011
- Article first published online: 23 NOV 2011
- Manuscript Accepted: 1 SEP 2011
- Manuscript Revised: 31 AUG 2011
- Manuscript Received: 2 AUG 2011
- power network;
- space weather
 Geomagnetically induced currents (GIC) are DC-like currents compared to power transmission frequencies. Consequently, it may be possible to reduce the magnitudes of GIC by installing resistive components or series capacitors into a power grid. We simulate the effects of neutral point reactors and series capacitors on GIC in the Finnish 400 kV network. Reactors add an additional resistance to earthing leads of transformers, and series capacitors block the flow of GIC in transmission lines. The geoelectric field impacting the system is considered to be uniform. The use of reactors does not necessarily reduce the GIC risk. Although the installation of reactors tends to decrease GIC on the average, maximum GIC may even increase. Assuming a reactor at all stations results in a 50% reduction of the maximum GIC compared to the situation with no reactors. With up to four series capacitors, the maximum GIC is reduced by 40% when they are optimally located. However, even small changes in the topology of the grid can cause large changes in GIC. A combination of reactors and series capacitors could in principle provide a way to diminish the GIC risk. This study also emphasizes the difficulty of preventing GIC problems by these means.