The relevance of the study lies in the need to ensure high reliability and troublefree operation of electric cables for power transmission lines and high-frequency information signals by non-destructive testing of their parameters.

Objective. To propose a new method for comprehensive diagnostics of electric cables, which allows increasing the efficiency of nondestructive testing of electric cable parameters by increasing the accuracy of testing and increasing the number of simultaneously monitored parameters.

Methods. Basic methods of theoretical electrical engineering were used for the theoretical justification of the new method, and digital systems for processing complex parameters of information signals were used in the development of circuit solutions.

Results. A conductometric method for non-destructive testing of parameters of the main cable elements has been developed and theoretically substantiated. For testing, two detachable cylindrical electrodes are applied to the examined section of a round metal core with dielectric insulation, which together with the examined part of the wire form a conductometric cell. It is shown that the electrical capacitance of this cell characterizes the electrical parameters of the wire, which are obtained from the measured information signal using the quadrature demodulation method. A structural block diagram for implementing this method has been developed. It is shown that the proposed technical solution allows recording an electric signal containing information on the current electric parameters of the controlled section of the electric cable, by which it is possible to assess the technical condition of its conductive elements and insulation. Based on this method, a method for operational tolerance control of the parameters of electric cables has been developed using the parameters of the reference section of the final length of the controlled cable without defects as a basic criterion.

Conclusion. The use of detachable metal cylinders as electrodes allows using these control methods both in cable manufacturing and on existing cable lines without violating their integrity in real time.

Relevance. A magnet is an important block in the design of measuring and analytical equipment based on nuclear (proton) magnetic resonance methods. A large volume of interpolar space and homogeneity of the magnetic field are desirable qualities of a magnet, directly affecting the accuracy of measurements. The Halbach magnetic assembly (HMA) is a promising type of magnet and is a priority for research for use in new generations of portable PMR relaxometers. They have smaller dimensions and weight but create a significantly greater magnetic field in the gap compared to dipole magnets of the same mass and distance between the poles. Therefore, the study and search for solutions to optimize the HMA parameters is an urgent task in the development of improved portable PMR relaxometers.

Objective. The aim of the work is to study and determine the factors influencing such important magnet parameters as: mass, dimensions, magnetic flux density and homogeneity of the magnetic field in the magnet gap and to develop mathematical equations to describe the influence of these factors on the magnet parameters. Based on the results of calculations and software modeling, the practical goal was to create an experimental prototype of HMA for evaluating and calibrating the quantities in mathematical equations.

Method. The applied method was the theory of magnetic combinations composed of identical magnets proposed by Klaus Halbach and other researchers in the field of magnets, based on which the corresponding mathematical equations are developed. ANSYS Maxwell magnetic field modeling software was used for preliminary evaluation of the theoretical calculations. An experimental study method was used in combination with statistical analysis to collect and process data during tests on the HMA prototype.

Results. The result is the development of a method for optimizing the HMA parameters by determining the influence of factors on the HMA parameters based on calculations and software modeling of the HMA prototype to test the optimization. As part of the study, a device for measuring magnetic field values in the range of 0–1.25 T with a resolution of 4 mV/mT based on a Hall sensor and an Arduino board was also developed, which complemented the research.

Conclusion. Based on the calculations of optimized parameters using a mathematical model, a prototype of the HMA was developed. It weighs 4.5 kg, dimensions 140×140×120 mm, and consists of 10 layers of cubic magnets stacked on top of each other. The developed HMA has a low price, is easy to manufacture and assemble, and has the flexibility of changing the design to adjust the magnetic field values in the gap. With a design of 10 layers, the magnetic flux density in the gap reaches B₀ = 0.344 T with inhomogeneity ΔB/B₀ = 2000 ppm in a volume of 6 cm³ in the center of the gap with a diameter of d = 30 mm. The value of the magnetic flux density in the HMA gap is like the value in the dipole magnets used in the PMR-NP1 and PMR-NP2 relaxometers, while the mass and dimensions are significantly less.

Relevance. The development of methods for controlling materials, products, substances and the natural environment should be completed by the validation stage. There is a well-known list of validation characteristics and recommendations for their evaluation for methods of controlling the composition of materials, products, substances and the natural environment. However, these descriptions and recommendations cannot be fully used in the case of methods for controlling the properties of materials, products, substances and the natural environment, in particular, the performance characteristics of fuels and motor oils.

The purpose. Development of a procedure for validating methods for controlling the performance characteristics of fuels and motor oils and confirming the possibility of its practical implementation.

Methods. The practical verification of the theoretical provisions was carried out during the validation of the method for controlling the thermal and oxidative stability of jet engine fuels under dynamic conditions. The essence of the method is to estimate the amount of deposits formed during the oxidation of fuel for jet engines under conditions of its pumping through an annular channel along a heated evaluation tube located inside the channel. Oxidation products accumulate as deposits on the surface of the evaluation tube, reducing its reflectivity, and on the filter element of the control filter, increasing the pressure drop on the control filter. Thermal and oxidative stability is monitored according to the following indicators: thermal stability index, the temperature at which deposits form, and the rate of pressure drop across the filter. The method is implemented on the basis of the DTS-4 laboratory installation.

Results. Based on the specifics of the procedure and the controls used, a set of validation characteristics of methods for monitoring the operational properties of fuels and motor oils is proposed: precision and accuracy of the control method; suitability of controls; range of values of controlled quantities; sensitivity of the control method to changes in the composition of fuel (oil); robustness of the method to small changes in control parameters; comparison of the newly developed method with already known methods having a similar functional purpose; the quality of modeling of the studied chemmotological process. To increase the efficiency of validation work, it is advisable to provide an additional stage for the development of a control sample with constant, guaranteed reproducible values characterizing the performance properties of motor fuels and oils (the internal standard of the control method).

Conclusion. The experience of validating the DTS-4 method shows that the developed procedure for validating methods for monitoring the performance characteristics of fuels and motor oils ensures that a sufficient amount of objective data is obtained that the new control method allows obtaining reliable information about a given operational property of the studied petroleum product.

Relevance of this research lies in addressing the issue of the voltage distortions’ negative impact on belt conveyor electric drive systems, caused by irregularities in the voltage waveform of power supply networks at coal mining facilities.

The purpose of this study is to create a mathematical and computer model that demonstrates the effectiveness of using a dynamic voltage restorer (DVR) in a belt conveyor multi-motor electrical drive system powered by an underground electrical network.

Methods. A multi-motor electromechanical system consisting of three BA280S4 low-voltage asynchronous motors with a total power of 330 kW making up the electric drive for the 2L100U-01 mining belt conveyor system is the object of this research. The study of the DVR operation in the electromechanical system under consideration was carried out by computer modeling using the MATLAB/Simulink® software.

Results. Simulation of system operation with the DVR and without it was performed for the following modes: studying the static stability of the system when the grid voltage reduces to 0.5 pu of its nominal value, studying the dynamic stability when the grid voltage fails for up to 8 seconds, the occurrence of non-sinusoidal and asymmetric voltage waveforms for 1-2 seconds. The simulation results confirm that, without the use of a DVR, the operation of the conveyor drive under voltage asymmetry conditions is characterized by multiple torque overloads, and in cases where voltage is reduced to 0.5 pu of the nominal value or is cut off for more than 8 seconds, there is a loss of speed stability. The use of the DVR ensures the restoration of the voltage waveform and the stability of the transient characteristics of drive speed and torque.

Conclusion. The conducted research illustrates that the DVR is an effective way to ensure stable and reliable operation of low-voltage multi-motor electric drives in high-performance coal mining belt conveyor facilities. The introduction of a DVR is reasonably recommended for coal mining enterprises.

Relevance. In the context of increasing requirements for air purity at industrial enterprises, electrostatic precipitators are of particular importance as an effective means of removing harmful particles from the air. The issues of their optimization remain relevant, since the level of purification and the cost-effectiveness of production processes depend on it.

The purpose. To conduct an experimental study of a wet single-zone electrostatic precipitator and determine the influence of design and operating parameters on its efficiency.

Methods. The electrostatic precipitator under study differs from classic electrostatic precipitators in the design of the precipitating electrodes. The precipitating electrodes are made in the form of round, rotating disks, which are half immersed in liquid for continuous cleaning. For the study, an experimental stand with a wet single-zone electrostatic precipitator was used, in which the key parameters were changed: supply voltage, distance between electrodes, radius of the precipitating electrodes and air flow velocity. The efficiency of the filter was estimated by measuring the concentration of particles before and after air purification. Each experiment was carried out for 20 minutes and repeated 5 times.

Results. Based on the test results, graphs were constructed of the dependence of the air purification efficiency of the electrostatic precipitator on the design and operating parameters. The experiments showed that the air purification efficiency decreases with an increase in the air flow rate and interelectrode distance, while an increase in the voltage and diameter of the electrodes improves the cleaning quality. Graphic dependences of the efficiency on the variable parameters were obtained, which made it possible to identify the optimal parameters.

Conclusion. Optimization of the parameters of the wet single-zone electrostatic precipitator helps to increase the air purification efficiency, which allows to reduce harmful emissions at production sites and improve the environmental friendliness and cost-effectiveness of production processes.

Relevance. The aim of the research is to improve the regulatory framework governing the procedure for determining the estimated load when summing up residential and public buildings of residential complexes.

The purposes. To analyze the graphs of electrical loads of transformer substations supplying a mixed load: apartment buildings, preschool educational institutions and secondary schools at different times of the year, days of the week, times of day, with subsequent development of proposals for updating SP 256.1325800.2016 "Electrical installations of residential and public buildings. Design and installation rules" in terms of the methodology for determining the total load of residential and public buildings of a residential complex.

Methods. In achieving the set goal, experimental, mathematical and statistical methods were used.

Results. The performed analysis of the load graphs allowed us to determine the time periods of maximum loads of transformer substations feeding a mixed load. The results of the analysis will be used to update the coefficients of simultaneity and noncoincidence of maximums for summing up the mixed load at the transformer substation.

Conclusion. The maximum load of transformer substations feeding only apartment buildings falls on the evening hours of weekends in the winter period (the load is lower on weekdays). On the contrary, the maximum loads of transformer substations feeding apartment buildings and preschool educational institutions, as well as apartment buildings and secondary schools, fall on weekdays. The estimated load of such transformer substations should be summed up with the load of apartment buildings on weekdays, taking into account the daily maximum load of educational institutions, for which it is necessary to provide a correction factor.

Relevance of the research lies in the need to solve the existing problems arising in the field of relay protection of 6-10 kV distribution networks during the introduction of distributed generation sources.

The purpose. To analyze the influence of distributed generation sources on the operating modes of a 6-10 kV distribution network. To identify the problems of operation of relay protection devices in 6-10 kV distribution networks in the presence of distributed generation sources connected to the distribution network using an inverter.

Methods. The review and analyze of literary sources, as well as the analysis of international information exchange data is carried out.

Results. The article describes the relevance of the topic, examines in detail inverter sources of distributed generation from the point of view of their connection and impact on the distribution network; a comparative analysis of the use of traditional sources and sources of distributed generation in distribution networks, an analysis of their influence on the magnitude of currents is carried out.

Conclusion. The use of inverter-based distributed generation sources creates problems for the operation of relay protection devices due to the limitation of inverter capacity and variability of network topology. At present, for the existing problems, there are scientific developments to solve them with their inherent advantages and disadvantages.

The purpose of this work is to study the influence of the operation of an arc furnace with a capacity of 30 tons on the quality of electricity by conducting experimental studies in the melting shop of the «Li Da Metal Technology» enterprise located in the city of Akhangaran. The object of study is the DSP-30 arc furnace, which is powered by a 30 kVA furnace transformer.

Results. The article presents the results of experimental studies to study the influence of the DSP-30 electric arc furnace on the operation of the electrical network in the smelting shop of the «Li Da Metal Technology» LLC JV enterprise and at the “Sanoat” substation, which supplies the smelting shop with electricity. Oscillograms of voltage and current changes were recorded before and during the melting process. The resulting oscillograms were analyzed using the Fast Fourier Transformation method.

Conclusion. Based on the analysis of the results of the above experimental studies, we can conclude the following: Electric arc furnaces are powerful nonlinear consumers with a dynamically changing electrical load. Therefore, when the furnace is operating in the melting mode, the voltage and current quality indicators sharply deteriorate, and the shape of the curves differs sharply from sinusoidal; The effects of deterioration in power quality indicators are clearly manifested in the secondary winding of a furnace transformer, in the buses of an industrial substation that supplies the station with electricity, then these effects appear in a much more damped state and can be recorded by special analyzers and oscilloscopes; When an electric arc furnace is operating in melting mode, the voltage value differs from the nominal value from 300 to 500 Volts. If the SVG power factor compensation device is not connected in dynamic mode, the voltage deviation can reach 5000 V. In conclusion, it should be noted that the electric arc furnace, as a nonlinear and highly variable consumer, has a significant impact on the deterioration of the quality indicators of electricity. From the point of view of the theory of electric energy quality indicators, this situation is a clear example of the negative impact on the quality indicators of a power source from the consumer.

Relevance. Optimization of CHPP modes is the most urgent task to increase profits on the wholesale electricity market. Free market economy forces CHPP’s to optimize its operation to achieve additional profits on Balancing electricity market.

The purpose is to increase marginal income of CHPP at the Wholesale Electricity Market by modes optimization.

Methods. The method of CHPP simulation modelling and the method of CHPP heat balances calculation were used. The digital twin of the investigated power plant was created in CAE United Cycle. United Cycle also provides the ability to calculate heat and mass balances of the CHPP in stationary modes. Other calculations were carried out by Microsoft Excel.

Results. The paper presents the results of fuel costs reduction due to return network water heat flows redistribution between steam turbine and combined cycle gas turbine. This result was achieved by solving the system of balance equations of power units of the investigated CHPP. A profit increase on the market with constant output of electricity and heat was achieved. The functions of additional power generation and fuel costs have been investigated. The cash flow of revenue and expenses was analyzed. The local extremum of the maximum profit on the balancing market was determined.

Conclusions. In a result of heat loads redistribution between steam and combined-cycle gas turbines, a reduction of total fuel consumption up to 7% was achieved. This ensures profit growth up to 60.59 thou.rub./h. The investigation of the optimal amount of power increase at Balancing market leads to profit growth up to 14.62 and 128.22 thou.rub./h for steam and combined cycle gas turbine, respectively.

Relevance. In all countries of the world, including Russia, there is a serious problem of fuel economy at energy enterprises directly related to the production of electric and thermal energy, as well as industrial enterprises producing various means of production. At thermal power plants (TPP), the specific consumption of conventional fuel is the most important indicator of the efficiency of the enterprise. The price (tariff) for consumed electric and thermal energy depends on this indicator, i.e., ultimately, the welfare of the population. purpose.

Purpose. To present the innovative concept of XPlate technology and present the results of the application of Xplate technology, which provides fuel economy.

Methods. Innovative NANO-technology fuel-saving results. The article describes the relevance of the topic, presents the results of the introduction of XPlate technology at Russian enterprises.

Results. The article describes the relevance of the topic, presents the results of the introduction of XPlate technology at Russian enterprises.

Conclusions. When using the XPlate technology method at specific enterprises, more complete combustion of fuel occurs, the temperature of the coolant increases in a short time, specific fuel consumption decreases, and contamination of the boiler heating surfaces decreases sharply.

Relevance of the study lies in solving environmental issues related to the discharge of wastewater at thermal power plants (TPPs) in Uzbekistan and Mongolia, which lead to the need to apply and improve methods for its purification.

The purpose. To consider the problems of wastewater treatment at thermal power plants. To conduct a study of modern technologies for wastewater treatment for their application at thermal power plants in Uzbekistan and Mongolia. To consider the simplest, most economical and dischargeless technologies for wastewater treatment at energy facilities.

Methods. In solving the problem, the method of calculating the volume of wastewater implemented by means of SMath® was adopted.

Results. The article describes the relevance of the topic, considers the problems of wastewater treatment at thermal power plants. The volume of industrial wastewater, which after preliminary treatment can be used for the technological needs of thermal power plants, is calculated. This paper presents data on the tests of new generation sorption materials: aluminosilicate sorbent EcoFerox, activated carbon grade AK47 and APT-1 at a concentration of petroleum products СPP ≈ 20 mg/dm³ based on diesel fuel, transformer and turbine oils.

Conclusion. A new scheme for cleaning and reusing wastewater for existing and planned thermal power plants in Uzbekistan and Mongolia has been developed. The proposed solution will partially solve the problems of water consumption at energy facilities in conditions of acute shortage of water resources. The obtained results showed that sorbents can be used for additional purification of wastewater from NP to the required MAC standards. It was established that the highest degree of purification of wastewater from NP is achieved when using filters with a two-layer load.

The aim of the work is to explore the possibility of using artificial intelligence to find leak detection using training data obtained using vibroacoustic sensors. The paper describes methods of continuous monitoring. Methods of periodic monitoring of leak detection in the pipeline are presented. Testing work was carried out on the laboratory stand. Methods for machine learning are considered, namely boosting, k-nearest neighbors, random forest method, multi-layer neural network method. An algorithm has been developed for compiling data arrays. The results of the program are shown.

The problem of high-viscosity oil production is becoming more urgent due to the depletion of traditional hydrocarbon reserves. This work evaluates the influence of various parameters of the downhole reactor, which plays an important role in the technology of extraction of high-viscosity oil. Special attention is paid to the length of the cylindrical heater, the heat flux density, the filtration rate and the radius of the heater. As a result, a formula was obtained for calculating the optimal length of the heater, depending on certain reactor parameters.

Purpose. To investigate and determine key parameters such as the length of the cylindrical heater, the filtration rate, and the radius of the cylindrical heater. To obtain a formula that will accurately calculate the optimal length of a cylindrical heater.

Methods. The study of theoretical aspects based on the physical laws that describe the processes of heat transfer, as well as on the thermophysical properties of high-viscosity oil. Comparison of various parameters of a cylindrical heater to determine the optimal length. results. In the course of the research, the relationships between the value x, m were established for the possibility of creating a reactor with the best characteristics at different values of heat flux density, filtration rate, radius of the cylindrical heater.

Conclusion. Studies have shown that the length of a cylindrical heater in a reactor depends on the radius of the heater, the linear density of the heat flow and the filtration rate. At heat flux densities of 1000 J/(m²·s), 1250 J/(m²·s), 1500 J/(m²·s), the length of the cylindrical heater at various values of heat flux density loss takes values in the range from 0.94 m to 2 m; at constant heat flux density losses – from 0.66 m to 3.3 m; It was found that as the heat flow increases, the length of the cylindrical heater decreases by 2 times, and as the filtration rate increases, it increases by 1.2 times. At different values of the radius of the cylindrical heater, its length remains unchanged, since the difference in length is insignificant.

Relevance. The paper presents the results of research to determine the influence of such raw material parameters as humidity and temperature in the pressing process on the physical and mechanical properties of the obtained briquette, as well as the analysis of furnaces of different designs during combustion of the obtained composite briquette consisting of solid wood waste and laminated paper waste containing synthetic polymers. The results of these studies will allow to use the obtained composite material with maximum energy efficiency when burning it in industrial power plants.

The goal of the research is to determine the effect of different values of humidity and temperature, in the process of pressing raw materials, on the final physical and mechanical parameters of the combined briquette, such as density and strength. Analyzing different furnace designs when burning the resulting fuel briquette, as well as analyzing the magnitude of compression of the briquette at different compositions of raw materials.

Methods. In this paper were used methods: analysis of thermoplasticity and moisture plasticity of polymer components of the raw materials used in the process of briquette formation with different compositions of raw materials; normative method of calculation of boiler units with different designs of furnace devices to determine the basic parameters of the boiler at combustion of combined briquette; construction of the dependence of the briquette compression value in the process of pressing on humidity and temperature with different compositions of raw materials.

Results. The paper presents the results of: physical and mechanical parameters of the briquette at given parameters of humidity and temperature; basic values of thermal calculation of the boiler unit with different designs of furnaces; the amount of compression of raw materials in the mold depending on the parameters of humidity and temperature, as well as, from the composition of raw materials.

Conclusion. The obtained research results will allow to use combined briquettes from wood waste and laminated paper waste, with maximum energy, economic and environmental efficiency in their combustion in boiler plants. The obtained combined briquettes have high physical and mechanical parameters under certain conditions and compositions of raw materials, which facilitates the process of transportation and storage of fuel.

The article analyzes the software and hardware complex of ISMDEGTU, designed to monitor and control the condition of the elements of the main technological equipment in the field of electric power industry. The ISMDEGTU system provides an opportunity to assess the current technical condition of the elements of gas turbine installations (GTU), which significantly reduces the risks of unscheduled shutdowns, allows you to predict equipment degradation and develop strategies to increase its efficiency and extend its service life. Special attention is paid to measures aimed at ensuring the security of the functioning of the ISMDEGTU hardware infrastructure and achieving information security goals, which is becoming especially relevant in the context of modern challenges.