Analysis of the impact of geomagnetic disturbances on the Austrian transmission grid

Transmission system operators are responsible for security and reliability of their grid. An important topic is the analysis of possible risks for the transmission system network. Because of problems with unexpected noise at some transformers, investigations were started, which gave an indication that DC could be the source of this noise. The paper presents investigations about geomagnetically induced currents (GIC) in the Austrian transmission system. Because of the particular geological structure of the country, the influence of GIC in Austria is higher than for the most other countries in Central Europe. A simulation model to compute GIC was set up and compared to the measured DC transformer neutral current.