The efficiency of a mining and processing plant depends on the level of complex mechanization of the production process. In mineral extraction, haulage is a major cost category, with haul trucks being the key component of the mining transportation system. To improve production performance, mining operations can increase their haulage turnover and reduce transportation costs, which necessitates making haul trucks more reliable. This can be done by improving their mean time to first failure (MTFF) indicators. This article analyzes the reliability status of the traction drive system inhaul trucks operating in the mineral resources sector. It provides a quantitative assessment of traction drive system failures resulting from part defects and discusses the associated repair costs. By examining failure data from 2018 to 2022 and the results of vibration tests performed on a diesel generator, the study reveals that the most expensive failures are associated with defects in the synchronous generator, which are primarily caused by elevated external vibrations. Based on basic vibration tests and vibration spectra tests at different operating modes, recommendations have been formulated concerning the generator’s robustness to external mechanical forces and the ways to increase the generator’s protection grade to prevent dust intrusion. The study also identifies the frequency range that poses the greatest risk of damage to the windings.
The urgency and necessity of choosing and justifying the structures of hybrid filter-compensating devices based on series and parallel active filters to improve the quality of electricity in the power supply systems of enterprises of the mineral resource complex is shown. Mathematical models of hybrid filter compensating devices based on parallel and series active filters have been developed. Based on these mathematical models, computer simulation models of the indicated hybrid structures have been developed. The results of simulation showed the effectiveness of the correction of power quality indicators in terms of reducing the level of higher harmonics of current and voltage, as well as voltage deviations. The degree of influence of filter-compensating devices on the power quality indicators, which determine the continuity and stability of the technological process at the enterprises of the mineral resource complex, have been revealed. It has been established that a hybrid filter-compensating device based on a parallel active filter can reduce the level of higher harmonics of current and voltage by more than 90 and 70 %, respectively, and based on a series active filter, it can reduce the level of higher harmonics of voltage by more than 80 %. Based on the simulation results, the possibility of compensating for the reactive power of a hybrid structure based on parallel active and passive filters has been revealed. The possibility of integrating hybrid filter-compensating devices into more complex multifunctional electrical systems for the automated improvement of the quality of electricity is substantiated, as well as the expediency and prospects of their use in combined power supply systems based on the parallel operation of centralized and autonomous sources of distributed generation.
The structures of systems with high-voltage cascade frequency converters containing multi-winding transformers and low-voltage low-power converters connected in series at each output phase of the load are considered. Low-voltage blocks contain three-phase diode or active rectifiers, DC capacitor filters, single-phase stand-alone voltage inverters and block disconnecting devices in partial modes (in case of failure when part of the blocks are disconnected). The possibilities of operation of cascade converters are determined, equations for correcting tasks to units in partial modes are given, tables of correction of tasks with estimates of achievable load characteristics are proposed. The results of experiments on the model of a powerful installation with a cascade frequency converter are presented, confirming the possibility of ensuring the symmetry of the load currents when disconnecting part of the blocks and the asymmetry of the circuit.
A complex of technical means and decisions for ensuring adequate level power safety at mineral resources enterprises has been developed, including voltage mode control method, power quality improvement method, method of ensuring dynamic stability for electricity-generating equipment, method of enhancing power supply reliability, distributive network structure control method, and method of combined use of alternative and renewable energy sources. The necessity of ensuring power safety for the objects of the mineral resources sector, from the technical point of view – with the application of modern achievements and developments in the area of electrical complexes and systems, has been proved.
The industrial test of active filter «Electon FSA» was carried out in field distributive network of JSC «Orenburgneft» TNK-BP with nonlinear load. The structure and operation principle of shunt active filter «Electon FSA-400» is presented. The curve shape registration and magnitude measurements of field network voltage and current were made at different operation mode of nonlinear load and studying active filter. The analysis of experimental data, which had been got from results of industrial test, was made. In the base of experimental data processing and analysis, the effectiveness of shunt active filter application in distributive networks of oil and gas enterprises was proved.
The power quality and electromagnetic compatibility have been studied and analyzed in power supply systems of oil-producing enterprises. Measurements were carried out at the 35,6 and 0,4 kV buses at the switching stations of oil-production plants by means of the «Resurs UF2M» measuring device. Deviations of power quality indexes from GOST 13109-97 standards have been revealed through these measurements. Recommendations have been developed, which allow enhancing power quality in power supply systems of oil-producing companies by means of on-load regulation of voltage adapter settings of power transformer and installing active and passive filters to equalize upper and lower harmonics. A structure of complex automated system to control power quality and power consumption is proposed for power supply systems of oil-production companies.
The policy of ensuring power quality in power-supply systems of gas-transfer enterprises, which allows to determine the type of electromagnetic disturbance, it’s source and technical solution for it’s compensation, is presented in the article. The simulation has been made in Mathlab Simulink to determine the active filter parameters. The non-linear load current, the active filter compensation current and the resulting current traces has been obtained during simulation. On the base of simulation’s results it’s supposed to choose the active filter parameters for power-supply system of gas-transfer enterprise and to design the technical guidelines for active filter applying.
The article deals with the problem of development and implementation of current and voltage curve correction systems in networks of mining and oil and gas processing enterprises using active filters based on IGBT transistors. The estimation of existing schemes of connection of active filters is given, their advantages and disadvantages are emphasized, the basic principles and features of their work are considered. The structure and control algorithm of the sequential active filter providing predictable compensation of harmonic components are given. The relations for its realization using the method of symmetric components and the theory of rotating coordinate systems are obtained.
The influence of converter load on distortion of current and voltage curves is evaluated. The indicators of electric power quality, on which the higher harmonics of converters have the greatest influence, including current curves for 6- and 12-pulse converters, are considered. The results of their Fourier series decomposition are obtained. The harmonic spectrum of these curves is analyzed. Relations reflecting the dependence of the order of harmonics on the converter pulses and allowing the selection of appropriate filters to reduce the negative influence of the converter harmonics on the operation modes of electric networks are given.
