Actually. The work addresses the topic of using electronic measuring devices in the drilling process of wells under particularly challenging and unique conditions in Antarctica. In the context of extremely low temperatures, characteristic of this region, the task is to ensure the reliable operation of electronics, which is critically important for the successful execution of drilling operations and obtaining accurate data. Special attention is given to analyzing various methods for protecting electronic devices from negative temperatures. Numerous approaches to thermal insulation are explored, and innovative materials are utilized to minimize the impact of cold air on sensitive electronic components.

Object. The aim of the work is to investigate current electronic measurement systems used in drilling wells under Antarctic conditions, as well as to conduct experiments on series temperature sensors using a cooling chamber.

Methods. The study includes thorough experiments with temperature sensors of various types and formats. Testing was conducted in specialized cooling chambers, allowing for the modeling of real conditions faced by devices in Antarctica. Furthermore, the study examines the impact of the sensor placement relative to the microchips, which can significantly affect their accuracy and reliability. An important part of the work was an experiment with electronics covered by a waterproof polymer coating. This coating not only protects the devices from moisture but also provides additional insulation against cold, which is of paramount importance in Antarctic conditions.

Results. Thus, the results obtained allow conclusions to be drawn about the most effective ways to protect electronic measuring devices for drilling in challenging climatic conditions, as well as opening new horizons for further research in this area.

The actuality of the study is to calculate the design of a cell to measure the characteristics of partial discharges (PD) occurring in gas defects within solid insulation. The size and volume of gas inclusions in the insulation are related to the PD characteristics that occur in these defects. Knowledge of the details of this relationship for defects of various sizes and shapes is necessary for proper diagnosis of the insulation condition of high voltage apparatuses and determination of their residual life. This connection is currently studied to an insufficient extent. The task of studying PDs is complicated by their small magnitude and the difficulty of separating PDs in gas defects from surface, corona PDs and extraneous random noises having a similar spectrum.

Objective of the work is to create an experimental setup with a measuring cell in which there are no corona and surface PDs, which complicate obtaining reliable results when measuring PDs in gas pores of a dielectric.

Methods. The calculation of the electric field strength in various cell designs by the finite element method in the ComSol-Multiphysice 6.0 program was used to solve the problem.

Results. The paper describes the relevance of the topic, presents the results of calculation of electric field distribution at different configurations of highvoltage electrodes, the results of PD measurements in control (defect-free) samples and samples with defects. It is proved that in the proposed design of the cell there are no surface and corona PDs on the electrodes, which allows us to study the characteristics of PDs in gas defects of insulation. It is established that PDs in a gas defect occur in the first and third parts of each period of a sinusoid of industrial frequency at the same potential difference between the electrodes. No shift of the PD occurrence voltage, which was predicted due to the assumed residual charge on the cavern walls, was found.

Relevance. The increasing electricity consumption in the private residential sector, driven in part by the growing use of electric heating, is leading to higher loads on 0.4 kV power transmission lines. Traditional standardized load profiles do not always reflect modern consumption patterns and conditions, which creates risks of inaccurate assessments of the electrical grid’s capacity and necessitates more precise modeling of grid operating conditions.

Purpose. To develop approaches for classifying consumers and identifying statistically significant patterns in electricity consumption in private residential areas for subsequent calculation of grid operating conditions.

Methods. The analysis was based on half-hourly electricity consumption data from 42 private houses, collected via an Automated Meter Reading and Management System (AMRMS). The data was cleaned using the three-sigma rule to remove gaps and outliers, and heat maps were used to identify non-representative consumers. The statistical significance of differences was determined using analysis of variance (ANOVA) and Tukey’s test. Based on median consumption values, consumer groups were formed (low and high electricity consumption). Data processing and visualization were performed using MS Excel, Python (Pandas, NumPy, SciPy libraries), and the Statistica software package.

Results. The analysis confirmed statistically significant differences in electricity consumption between most of the houses (F = 2065.4, p < 0.001). Tukey’s test showed that within each group, homes exhibited relatively stable energy consumption values, while intergroup comparisons revealed substantial variations in electricity usage. As a result of the study, two consumer types were identified: "low" and "high" consumption groups. The high-consumption group exhibited distinct evening peaks (18:00–22:00), whereas the low-consumption group had a more evenly distributed load profile.

Conclusion. The application of statistical analysis methods to electricity consumption data enabled the simplification of household classification into two main groups and the development of typical consumption profiles. These results were integrated into the LineCapacity software, facilitating grid operation calculations and reducing the risk of misjudging the available power transmission capacity. A promising research direction is planned, focusing on expanding the dataset on residential electricity consumption. This will allow for the consideration of seasonal factors and the development of simulation modeling mechanisms for various consumer groups.

Relevance. The article investigates the issues of evaluating the reliability parameters of contacts of low-voltage switching devices (LWSD) installed in low-voltage electrical networks of power supply systems of industrial enterprises.

Object. To investigate the main parameters of reliability of LWSD contacts using the statistical method and to analyze the physical processes in the contact connections.

Methods. To improve the accuracy of determining the LWSD failure rate, it is proposed to introduce correction factors that take into account the influence of the main influencing factors on the studied LWSD. The study of the switching life of contacts was performed by analytical and graphical-analytical methods.

Results. On the basis of the conducted researches it has been established that the graphical-analytical method with taking into account correction factors can be recommended to increase the reliability of LWSD parameters estimation. The value of the number of switching cycles of the device, after which the occurrence of failure is most likely, depends on its loading factor. It is revealed that for the studied devices after expiration of 25% of the resource number of switching cycles the probability of failure-free operation becomes lower than the permissible value.

Conclusions. The research results show that after 3-5 years of operation the probability of failure-free operation of the observed LWSD decreased to the value less than 0.85. The obtained results are recommended to be taken into account when drawing up schedules of preventive maintenance in the electrical networks of inhouse power supply.

Relevance. The efficiency and reliability of the relay protection system is influenced by many factors, such as: failure of the power switch, malfunction of the relay protection device components, errors in the operation of the current measurement, etc. These failures can lead to a complete failure of the protection system or incorrect protective action and, in the case of a short circuit, often result in damage to the protected object. Therefore, the development of more advanced methods for detecting failures in the protection system elements is crucial. THE

Purpose. The purpose of the article is to briefly analyze the problem of reliability in relay protection system in the event of a failure of protection elements, develop a new algorithm for the operation of longitudinal differential relay devices that detects current transformer failure (CT) on any side protected element, and recognizes network mode. The proposed algorithm allows relay protection devices to adapt when a CT failure is detected in each cycle, thus increasing the reliability of the protection system.

Methods. The algorithm is developed using mathematical logic methods. Protection devices utilize inter-station communication channels to exchange information with adjacent devices. Additionally , these devices automatically adapt their operating algorithm to the type failure that occurs, and reconfigure protection zones accordingly.

Results. The article examines the problem, and develops an algorithm for the automatic detection of failures in current transformer and relay protection circuits. This algorithm is based on Kirchhoff's first law and utilize an intersubstation information network. The proposed algorithm not only enables the unambiguous detection of such failures, but also allows for the instant adaption of differential relay protection zones when necessary, ensuring the speed relay protection is maintained . The algorithm has been validated through testing in the PSCAD/EMTDC program using a case study of busbar differential protection.

Conclusion. As a result of the research, significant findings have been obtaine that can be enhance the reliability of the digital relay protection system in the event of failures in protection elements.

The paper considers the solution to the problem of multicriterial optimization of the high-voltage test transformer design using the NSGA-II algorithm. The optimization criteria are the mass of active materials, losses, and the ratio of the capacitance between the first and second layers of the secondary winding to the capacitance between the penultimate and last layers of the secondary winding. The calculation method for the transformer design used in the optimization is presented. An example of optimization of the high-voltage test transformer design is given. It is shown that the use of the NSGA-II algorithm made it possible to significantly reduce the mass of active materials and losses in the transformer compared to the basic version calculated using the traditional method.

The growth of modern industry directly connects to the introduction of a wide variety of electrical apparatus and complex electronic devices. This growth inevitably leads to a significant increase in electricity consumption. As a result, industrial facilities require an uninterrupted power supply. Voltage sags present a serious obstacle in this process, causing disruptions in operations and equipment failures, which can lead to costly downtimes and increased maintenance expenses.

Objective. This study aims to analyze the issue of ensuring voltage stability at industrial enterprises in the context of voltage sags.

Methods. The research includes an overview of existing engineering measures designed to neutralize voltage sags. These measures encompass both hardware solutions, such as UPS systems and voltage regulators, and software strategies that monitor and manage electrical loads.

Results. The article discusses the relevance of the topic, defines voltage sags, and outlines the main characteristics of this phenomenon, including depth and duration. The analysis presents data on the primary causes and effects of voltage sags at various enterprises. It evaluates available means and methods for minimizing the impact of voltage sags on technological processes, thereby enhancing operational efficiency.

Conclusion. Each method for addressing voltage sags comes with its own advantages and disadvantages. Moreover, some methods influence the depth of the failure while others affect its duration. Users should justify the choice of method based on the specific requirements of each electrical system, ensuring compatibility with other technological processes during the design phase. By thoughtfully applying these strategies, businesses can enhance their operational resilience against voltage disturbances.

In this study, a genetic algorithm-based design optimization methodology for a permanent magnet synchronous motor (PMSM) is developed to improve energy efficiency and reduce torque pulsation.

The objective of the study was to determine the optimal motor geometric parameters, including magnet wrap angle, magnet thickness, stator tooth width, slot depth, and air gap, taking into account technological constraints and electromagnetic characteristics.

The methodology is based on a combination of analytical modeling of magnetic circuits and a genetic algorithm implemented in MATLAB with a multi-objective fitness function that takes into account torque, pulsation, and efficiency.

The results demonstrate that the proposed approach achieves significant performance improvements: an 8.9% increase in torque, a 40% decrease in pulsation, and a 3.5 percentage point increase in efficiency compared to the baseline configuration. It was found that the optimal configuration is achieved with a magnet coverage angle of 72° and an air gap of 0.85 mm, which confirms the need to use modern optimization methods to find non-trivial technical solutions.

Conclusion. The results obtained are of practical importance for designing energyefficient motors, reducing development time. The study contributes to the development of computer-aided design methods for electrical machines, demonstrating the effectiveness of genetic algorithms for solving complex multi-criteria problems of electromechanics.

Objective. To conduct a dynamic analysis of the factors affecting the reliability of inverters used in large-scale solar power plants and to develop predictive monitoring algorithms for their technical condition.

Methods. The study employed methods of systematic classification of reliability factors, thermal, electrical, and mechanical analysis, as well as machine learning techniques based on autoencoders for anomaly detection. Sensor technologies and IoT architecture were utilized for real-time data acquisition and processing.

Results. A classification of factors influencing inverter reliability was developed, including an assessment of their sensor monitoring capabilities. An adaptive system architecture for technical condition analysis was constructed, incorporating a block diagram of dynamic monitoring. An Autoencoder + Threshold-based Anomaly Detection model was proposed to evaluate the inverter health index in real time, enabling early detection of potential failures.

Conclusion. The proposed approach enhances the reliability and operational efficiency of centralized inverters by implementing an intelligent monitoring system. The use of predictive analytics and sensor-based architecture contributes to reduced maintenance costs, improved operational stability of solar power plants, and preemptive failure detection.

Relevance. In the context of the digital transformation of the electric power industry, the urgency of developing distributed control systems for the condition of electrical network equipment based on forecasting the operating time for a defect with the determination of the adaptive frequency of preventive action is increasing.

The purpose. To justify the expediency of creating and applying a similar electrical installation repair management system based on thermal imaging control (TIC) statistics as an alternative to local on-line monitoring systems based on various temperature sensors. To develop a predictive mathematical model to determine the operating time for a developed defect in the equipment. To form a methodology for calculating the adaptive frequency of equipment withdrawal for repair according to technical condition.

Methods. The research uses methods of statistical data processing and statistical hypothesis testing, the formation of homogeneous Markov models with continuous time and numerical modeling in the MathCAD software environment.

Results. The article reveals the relevance of the topic, outlines the methodological aspects of a distributed predictive control system for repairs of electrical network equipment, shows its advantages over local control systems based on modern temperature sensors, suggests models for predicting operating time for a developed defect in equipment and the frequency of its preventive repairs according to the actual technical condition. The calculation of the frequency of preventive maintenance of CTS-6/0.4 kV transformers of one of the electric utilities is given based on the forecast of operating time for a developed defect, illustrating the possibilities of the claimed technique.

Conclusion. The proposed system of distributed predictive control of the technical condition of electrical network equipment based on operating time for a defect, unlike local temperature control systems based on modern sensors, has great functionality with significant cost savings. Its use is guaranteed to ensure the effectiveness of equipment prevention management due to the high reliability of the forecast of operating time for a defect and the determination of the adaptive frequency of preventive action.

Methods. The algorithm used for modeling consists of several stages: first, random variables rk and xk are set, which remain constant at all subsequent stages of modeling. For each case, a random value of loads and generation is set and a system of equations is solved to determine the voltage levels along the line and total losses.

Results. The article describes the relevance of the topic, considers the features of the influence of active and reactive power regulation on the steady-state modes of the electrical network. For modes 3 and 4, the entire part of the curve from the extreme left point (corresponding to the best power quality) to the point of reaching the global minimum (when losses are minimal) represents a possible area where a compromise can be found between loss reduction and voltage drop by adjusting K. Comparison of different modes shows that maximum flexibility is achieved in mode 4, when high penetration of renewable energy sources leads to overproduction of electricity.

Conclusion. Summarizing the simulation results, it can be said that the reactive power flow control scheme on distributed PV grid inverters is quite simple and effective. Reactive power flows are controlled according to local values of active and reactive power consumption. The scheme contains one generalized adjustable parameter for balancing between local demands in order to minimize the power flow and maintain a good level of power quality.

Relevance. This study addresses the need to develop a method for modeling the load profile of electric vehicle charging stations (EVCS) while accounting for parameter uncertainties, including the stochastic intensity of electric vehicle (EV) connections over a given period.

The Purpose. Analyze challenges in modeling EVCS load profiles under uncertainty. Develop a simulation method for EVCS load profiles that incorporates multiple stochastic components. Simulate load profiles reflecting the intensity of charging start times using empirical data. Evaluate EVCS load uncertainty, model convergence, and sensitivity to input parameter variations.

Methods. The study analyzes existing methods for modeling EVCS load profiles. A Monte Carlo method, implemented in MatLab®, was used to construct a mathematical model of the EVCS load profile.

Results. Experimental data on the number of connected EVs are processed to derive an average daily EVCS load profile. A combined probability distribution law, aligned with empirical data and reflecting EV connection intensity, is applied. A parametric model is developed to generate the temporal load profile of EVCS, incorporating key uncertainty factors: charging start time, EV power consumption, charging duration, and the number of EVs.

Conclusions. A method and model for simulating EVCS load profiles are proposed, enabling the generation of temporal power profiles under input data uncertainty. The model can be applied to plan EVCS placement, evaluate power imbalance and select parameters for energy storage systems to integrate EVCS and ensure their stable operation in distribution grids.

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 costeffectiveness of production processes.

The Purpose. The purpose of this work is to develop a program that uses the finite element method to analyze the stress-strain state of a membrane coupling capable of compensating for axial, angular, and radial misalignments of the shafts in a gas pumping unit.

Methods. The finite element method of the ANSYS software package underpins the algorithm’s development.

Results. The article describes the relevance of the topic and examines the features and advantages of the chosen membrane coupling design. The developed universal numerical algorithm allows to estimate the strength of the coupling structure transmitting torque, made of various materials. The program helps to find zones of increased stress and extreme values of rotation speed, as well as the ability to compensate for the misalignment of the turbine and supercharger shafts. The program allows you to quickly change the initial geometric parameters with automatic construction of a new 3D model.

Conclusions. This research focuses on improving the efficiency and reliability of gas pumping units and the gas transmission system. Calculation results confirmed the claimed properties of the membrane coupling under various operating conditions, including its ability to compensate for shaft misalignment. Further program development will involve analyzing stresses from the variable (cyclic) component of the torque, and constructing a mathematical model of the shaft line vibrations, taking into account bearing damping.

The relevance of the research lies in the development of a concept for transitioning to hydrogen fuel in the heating supply system of the Murmansk region. The Murmansk region possesses unique natural resources and harsh climatic conditions, making it an exceptional area for the implementation of hydrogen technologies. The article presents the results of modeling the operation of wind power plants (WPP), projected generation capacities, and the prospects for using hydrogen in the heating supply system of the Murmansk region. This work examines the possibilities of utilizing "green" electricity generated from renewable energy sources—nuclear, wind, and hydroelectric power plants—to replace traditional fuels such as diesel and fuel oil. Objective: To address the fuel supply issue in the Murmansk region and develop a technology for producing hydrogen fuel, followed by its combustion in the region's existing energy equipment. Methods: The Winpro software was used for modeling the operational modes of equipment, with subsequent hourly power distribution in the Smartren software suite.Results: The conducted research demonstrated the feasibility of modernizing the existing infrastructure, including boiler houses and electrical networks, for the implementation of hydrogen technologies. For example, co-combustion of hydrogen with traditional types of fuel is proposed, which will reduce the specific consumption of hydrocarbon fuels, lower the carbon footprint, and decrease harmful emissions. The study also analyzes the carbon footprint generated from the combustion of various types of fuel, showing that "green" hydrogen has significant advantages in this regard. It is shown that the transition to hydrogen technologies can not only improve the environmental situation in the Murmansk region but also become an economically viable solution that attracts investments and fosters the development of new technologies in the region. Hydrogen can partially replace traditional fuel in the form of fuel oil; considering the transportation of fuel oil to the boiler house, its fuel preparation, and emissions from fuel oil use, the cost of hydrogen will be competitive. Thus, this research, using the example of the Murmansk region, demonstrates the potential for implementing hydrogen technologies for the sustainable development of the region.

The use of natural gas fuel cells can significantly increase the sustainability and efficiency of energy supply to private homes, provide important environmental benefits and reduce energy costs. However, the widespread use of natural gas fuel cells in residential buildings is limited by a number of factors, among which the most significant is the high cost of a fuel cell. The study analyzes energy consumption for two energy supply systems, a standard system based on a double-circuit gas boiler and a system using a solid oxide fuel cell powered by natural gas. purpose. To determine the economic feasibility of using solid oxide fuel cells (TTE) on natural gas in private residential buildings.

Methods. Data on energy consumption of the analyzed building was collected using meter readings. Based on these data, annual schedules of electricity and natural gas consumption were created. The scheme of the energy supply system of a private house using TTE, as well as the equation of the mathematical model of natural gas consumption by the system with TTE, were based on the laws of conservation of energy and mass, as well as using statistical methods for analyzing existing research in the field of fuel cell applications. results. During the study, a graph of the dynamics of energy prices by month was compiled for the two compared systems. conclusion. The introduction of energy supply systems based on solid oxide fuel cells (TTE) powered by natural gas in residential buildings may be a promising solution. A comparison of a system based on a double-circuit gas boiler without a TTE and a system with a TTE on natural gas showed that monthly savings range from 24% to 47%, with an average annual value of 34.5%. For a family of three living in a two-storey brick house in Kazan, Republic of Tatarstan, this means an annual savings of 25,080 rubles.

Relevance. Study of heat exchange processes in capillary-porous natural coatings created by thermal spraying of powders during their application with a thermal tool. Quartzite, granite, teshenite, tuff and marble rocks are chosen as natural materials. A thermal tool with spin detonation jet was created and the technology of powder production by a new method was developed.

Methods. The thermo-tool due to the automatic device allows controlling the mode of coating creation by changing the burner power and torch length. The displacement scheme of tool feeding and the methodology of experimentation were developed. Powders were prepared in special molds from the system of conjugate elliptical surfaces and different eccentricity. The technology increases the powder yield of (0÷2)×10^-3 m class and increases the degree of powder hardening. The combustor was afterburning on the coating with oxidizer excess coefficient 0.6 ÷ 0.8, specific loads increased up to six times and amounted to (2÷15)×10⁶ W/m². The ductile rocks were subjected to melting.

Results. The transverse velocity of the ignition section of the spin detonation plume was close to the detonation velocity and twice the speed of sound in the jet. The thermal stress limit region for the coatings while maintaining superheat of (20÷75) K was superior to boiling in thin films, large volume, and heat pipes. Studies by holographic interferometry showed that the point of reference is the residual deformation defined by a network of small cracks that do not disappear when the thermal load is removed.

Conclusion. A nonlinear particle displacement curve was found, and detonation spraying reduces powder particle fracture along the interfaces of unmelted particles. The natural material provides high erosion resistance of the coating. The joint methods of investigation by means of holography, highspeed filming and analytical solution allow to specify the mechanism of coating creation and to obtain calculated values of heat fluxes and stresses.

Relevance. The complexity of the structure of enterprises in the pulp and paper industry is determined by the large number of elements in the thermal technology schemes of production, reverse flows, connections with the environment in the form of consumed fuel and energy resources and waste energy in the form of secondary energy resources. For such enterprises, there may be many options for improving energy efficiency with the inclusion of energy-saving equipment. Therefore, the use of a structural and thermodynamic approach to the analysis of thermal technology schemes is proposed to select an effective option. purpose. Development of an algorithm for structural and thermodynamic analysis, which makes it possible to overcome the ambiguity of the initial data and calculate reliable values of the parameters of external energy sources, data on which are often not available in pulp and paper industries, but are necessary to assess the thermodynamic efficiency of waste energy use.

Methods. To achieve this goal, a systematic approach is used using matrix analysis and Boolean algebra, the exergetic method of thermodynamic analysis, and software has been developed that combines these methods. results. For the thermal technology scheme of paper production, the optimal sequence of thermodynamic calculations with a minimum number of iterations/assumptions in the sections of the conditional flow gap of the scheme has been determined. As a result of the thermodynamic analysis, data were obtained on the thermal and exergetic efficiency of the elements of the thermal technology scheme of pulp and paper production, as well as data on flows, the use of which will ensure the organization of an optimal system for recycling secondary energy.

Conclusion. The developed software for structural and thermodynamic analysis was implemented to evaluate the thermodynamic efficiency of the thermal technology scheme of paper production. The minimum number of flows of the scheme has been revealed – 20 flows, the conditional break of which makes it possible to fully perform the thermodynamic calculation of the scheme with a minimum number of iterations and determine reliable values of the energy flow parameters. The results of the thermodynamic analysis showed that the lowest exergetic efficiency is for devices with such discharge flows as the heat of cooling of the upper product of the columns, exhaust air after the drying process in a paper machine, recycled water, and wastewater. Therefore, it is in such devices that the energy of the discharge streams of the greatest exergetic potential should be returned to increase the thermodynamic efficiency of the heat technology scheme as a whole.