System analysis of electric power quality as a factor of sustainable development of the mining and transport complex

Introduction. Power quality is critical to ensuring the sustainable and reliable operation of mining enterprises. At the molybdenum mine, where electric locomotive haulage is a key process, a significant problem has arisen: reduced electrical equipment reliability caused by higher harmonic distortions in the 6 kV network from numerous traction converter substations. The purpose of the research: to conduct a systemic analysis of the levels and spectral composition of higher harmonics in the mine’s 6 kV networks to develop evidence-based measures to improve power quality and the energy efficiency of the mining and transport complex. Objects and methods. The study focused on the 6 kV cable network of the molybdenum mine, fed from the 110/6 kV Stolnya Main Substation and loaded by ATP-500 traction substations. A method of in-kind measurements using the PKK-57 integrated monitoring device at characteristic points of the network was applied, supplemented by an analytical decomposition of the current and voltage curves in a Fourier series to identify harmonics of both the canonical and non-canonical series. Results and discussions. It was found that although the voltage non-sinusoidality coefficient at the main substation does not exceed the standard (0.355%), the current loads of traction substations show a significant excess of permissible harmonic levels, aggravated by the presence of non-canonical components due to the asymmetry of rectifier bridges. The predominance of the 5th and 7th harmonics, creating a risk of resonance phenomena, was revealed. The main causes of asymmetry are operational in nature. The impact of the identified distortions on network reliability and losses is discussed. Conclusion. A practical methodology for monitoring and verifying rectifier units has been developed. Its implementation will significantly reduce harmonic levels, improve power supply reliability, and increase energy efficiency, all in line with the principles of sustainable development in mountainous regions. Prospects for further research. Future plans include the development and feasibility study of filter compensating devices, as well as the creation of a digital network model to predict harmonic distortion when operating modes and load structure change

Electric power system · Electrical network · Harmonic · Harmonics · Power factor · Power quality · Reliability (semiconductor · Traction (geology · Traction substation · Voltage · Electric Power Systems and Control · Industrial Engineering and Technologies · Railway Systems and Energy Efficiency