Diagnostics of geomagnetically-induced currents in high-tension electric transmission lines

The problem of geomagnetically-induced currents (GIC) effect on electrotechnical systems is topical as long as uninterrupted power distribution is critically important for all the spheres of human activity. Our investigations showed the possibility of GIC diagnostics based on the estimates of industrial current higher harmonics and showed that even harmonics correlate with the Earth magnetic field changes in a greater degree. However, the measurements carried out in 220 V network showed low and not always univocal correlation of the processes. Thus, we propose a technique for diagnostics of geomagnetically-induced currents in high-tension electric transmission lines**.