Organization of Monitoring of Even Harmonics Amplitudes in the Electricity Networks of the Altai Republic as an Indicator of Space Weather

The system for monitoring the amplitude of current even harmonics in electric networks based on an induction sensor and a digital recorder is developed and constructed. The induction sensor is connected to the differential inputs of 24 bit analog-digital converter directly. Registration is carried out with a frequency of 1 kHz, the maximum sensitivity is achieved at the frequency of the 6th harmonic and is 1.3 mV/nT. For storage efficiency, the recorder records the first 15 seconds of each minute synchronized from the PPS modem in UTC time. Monitoring of even harmonic amplitudes is organized at the Ininskaya electrical substation in the Altai Republic since 28 July 2023. A signal–to–noise ratio is 63 dB. The appearance of a correlation (R=0.3...0.5) between the amplitude of current even harmonics and the rate of change of the horizontally oriented components of the geomagnetic field during moderate magnetic disturbances of 05 August 2023 was found. It indicates the influence of geomagnetically induced currents on the power system of the Altai Republic. The maximum value of the correlation coefficient was observed for the 6th harmonic. It is planned to accumulate further the information during the increasing activity of the current solar cycle.