Analysis of power quality indicators in the development of a smart grid at an underground mine

Abstract

The paper presents the results of experimental studies of power quality indicators in the power supply system of anunderground iron ore mine when planning the development of a smart grid. Measurements were taken using specialised equipment atpoints in the power grid with voltage levels of 6 and 0.4 kV. Key power quality indicators were analysed, such as voltage deviation,total harmonic distortion of current and voltage, and frequency deviation. It was found that in the 6 kV network, the voltage drop iswithin the maximum permissible level (+/-10 %). In the part of the power grid with a voltage level of 0.4 kV, critical voltagedeviations occur that exceed the standardised limit. The total coefficient of harmonic distortion of voltage and current, as well as thefrequency, are within normal limits here. Based on the data obtained, a systemic nature of voltage quality problems was identified inthe nodes of the underground mine's power supply system located far from the surface. This requires a detailed technical audit of thecondition of cable lines and transformers, as well as an assessment of the possibility of using specialised means of compensating forvoltage drops (e.g. dynamic voltage restorers, static compensators, etc.).Such measures are necessary to ensure stable and reliablepower supply in the context of developing a smart power grid for an underground iron ore enterprise, which is crucial for ensuringreliable power supply to underground power receivers and improving the competitiveness of mining production.