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[Objective] With the continuous improvement of metro network, the names of switches in the power supply system at all levels can no longer accurately mark the systems they belong to, meanwhile the duplicated and insufficient numbering also occur. Therefore, it is necessary to optimize the switch numbering in metro power supply system. [Method] The current situation of switch numbering scheme for the power supply system in Xi'an Metro, for example, is evaluated. Compared with the power supply systems for metros, electrified railways and the State Grid in other cities of China, the problems existing in the scheme are analyzed and specific solutions proposed. Starting from the characteristics of the power supply system switch numbers, considering their uniqueness and relevance, and combined with the planning of metro lines, the power supply system switch numbers are optimized and a new numbering method is proposed based on an analysis of its feasibility. [Result & Conclusion] The optimized switch numbering scheme for metro power supply system largely solves the numbering problems such as duplicate, disorder, poor organization and regularity. At the same time, it also realizes feeder and busbar classification, and voltage level identification, ensuring the uniqueness of the equipment names and numbers within each network area. [ABSTRACT FROM AUTHOR]

This paper designed a composite power supply system to solve the problems of insufficient endurance of electric tractors, high energy consumption due to high randomness of power system discharge and imperfect capacity configuration, the study designed a composite power supply system based on battery and supercapacitor power supply. Aiming at the problem of poor dynamic load adaptability, a three-stage load power segmentation rule was designed, and the functional relationship between the power division parameter and the load statistics was established. Aiming at the phenomenon of poor discharging effect of the energy storage system due to changes in the working conditions of the electric tractor under the traditional fixedthreshold strategy, a fuzzy logic-based adaptive adjustment strategy for the discharging threshold was proposed on the basis of double closed-loop control. In addition, considering the differences between storage batteries and supercapacitors in terms of power density, energy density and price, a hybrid energy storage system capacity configuration method that considered the optimal energy saving rate and comprehensive economic effect was proposed. The capacity configuration objective function containing the whole life cycle cost of the energy storage device and the system power consumption cost was constructed, the energy saving rate results of the no-threshold control strategy and the threshold control strategy in this paper were analyzed separately, the genetic algorithm was used to find the optimal solution for the capacity configuration objective function, and the impact of the energy saving rate constraints on the capacity configuration results was analyzed. In addition, the proposed discharge threshold adaptive adjustment strategy was simulated and analyzed, and the simulation test was completed on the laboratory 10 kW load power supply simulation system to verify. The results showed that the energy saving rate using the fuzzy logic adaptive threshold control strategy in this paper was improved by 3.09% and the hourly power consumption was reduced by nearly 9.5% compared with the traditional energy management strategy without threshold, at the same time, the output voltage of the power supply system was 527 V when the power fluctuated greatly and the output voltage of the power supply system was 520 V when the power fluctuates was smooth, which improved the output voltage stability of the energy storage system. Implementation of the designed energy management strategy for composite power supply system using genetic algorithm can achieve better real-time energy management with lower computational cost. [ABSTRACT FROM AUTHOR]

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The integrity of the 12 V dc power distribution system on a vehicle is essential to guarantee continuous power supply to safety-relevant consumers. Safety-relevant consumers are critical loads, for example, electric power steering, braking systems with functionalities like Anti-Lock Braking or Electronic Stability Control, and autonomous drive systems. To prevent insufficient power supply for safety-relevant consumers due to an increased wiring harness resistance, a novel diagnostic approach is developed to determine the condition of the power distribution, especially the electrical resistance. The influence of measurement errors and bus commutation on the estimation is investigated by using a simulation. By using the diagnostic, a resistance determination in the milliohm range with a standard deviation of σ = 0.3 m Ω can be achieved under realistic conditions. This ensures that failures in the wiring harness can be identified, avoiding cascading effects and minimizing recalls. Compared to the state of the art, redundancies, costs, and weight can be saved with the proposed diagnostic system based on electrical resistance estimation. [ABSTRACT FROM AUTHOR]

This paper describes the upgradation of power supply systems for the improved performance of a small spherical tokamak (MT-I) with an aspect ratio of 1.67 in operation at the Pakistan Tokamak Plasma Research Institute (PTPRI), Islamabad. Three mutually independent power supplies are designed to generate current pulses of desired shape and magnitude in central solenoid (CS), toroidal field (TF) and vertical field (VF) coil systems. The main parts of a power supply are capacitor banks as energy storage devices, ignitrons and thyristors as fast switches for controlled power switching. A double capacitor bank topology with enhanced second capacitor bank voltage is found to be suitable for CS to improve the plasma startup conditions. Simulations are performed in MATLAB Simulink for confirmation of the designed power supply system. The Rogowski coil and current transformers are employed to measure plasma current and the coil's current waveforms during the experiment in the presence of hydrogen as working gas. An ocean spectrometer and a photron high-speed camera (SA-8) are used for optical measurements and fast plasma imaging. An improvement in startup conditions is observed, enhancing the plasma current duration and light emission intensity recorded in the high-speed camera masked with a Hα filter. [ABSTRACT FROM AUTHOR]

［Objective］ With the continuous improvement of metro network, the names of switches in the power supply system at all levels can no longer accurately mark the systems they belong to, meanwhile the duplicated and insufficient numbering also occur. Therefore, it is necessary to optimize the switch numbering in metro power supply system. ［Method］ The current situation of switch numbering scheme for the power supply system in Xi’an Metro, for example, is evaluated. Compared with the power supply systems for metros, electrified railways and the State Grid in other cities of China, the problems existing in the scheme are analyzed and specific solutions proposed. Starting from the characteristics of the power supply system switch numbers, considering their uniqueness and relevance, and combined with the planning of metro lines, the power supply system switch numbers are optimized and a new numbering method is proposed based on an analysis of its feasibility. ［Result & Conclusion］ The optimized switch numbering scheme for metro power supply system largely solves the numbering problems such as duplicate, disorder, poor organization and regularity. At the same time, it also realizes feeder and busbar classification, and voltage level identification, ensuring the uniqueness of the equipment names and numbers within each network area.

In the process of designing in-plant power supply systems, it is necessary to determine their rational redundancy. The reliability of the power supply system has been established for the following variants of the circuit of two-transformer 10/0.4 kV substations: without redundancy; with redundancy (when installing a sectional switch); with double redundancy (when installing a sectional switch and a backup jumper for 0.4 kV). The calculation data have shown that the reliability of the circuit without redundancy is 1.87 times lower compared to the circuit with redundancy and 3.17 times lower than with the circuit with double redundancy. Graphic dependencies of the mean time between failures of power supply circuits with two-transformer substations from different rated capacities of shop transformers have been obtained for three variants: without redundancy; with redundancy; with double redundancy. The optimal condition is to use a smaller number of transformer substations (respectively, transformers) while maintaining the load factor of 0.8. When comparing the graphs, it has been found that the longest mean time between failures is achieved with double redundancy, and the shortest – with no redundancy. The research results can be recommended for use in the process of designing in-plant power supply systems to assess and improve the reliability and efficiency of equipment operation.

The development of the shipbuilding industry involves increasing the competitiveness of manufactured products, replacing obsolete electrical equipment, and increasing the efficiency of power supply systems. The introduction of the latest technologies reduces the weight and size of equipment, expands their functionality, but these technologies are based on nonlinear and asymmetrical power consumers, which causes a negative impact on the power grid. The power supply system of the Baltic Shipyard "Yantar" is characterized by a significant share of nonlinear, asymmetrical loads, often single-phase. An integrated approach to the analysis of the plant's power supply system included experimental studies of nonlinear power consumers, during which a high level of higher current harmonics (3rd, 5th and 7th orders) was established. One of the effective methods for reducing zero-sequence voltage asymmetry is to replace a transformer with a Y/Y0 winding connection diagram with a Δ/Y0 diagram. Circuit and technological solutions (separation of nonlinear loads to a separate bus system; increasing the phase of semiconductor converters; connecting a nonlinear load to a system with greater short-circuit power) and filtering devices (narrow-band filters, filter-balancing devices and active filters) are used to increase the efficiency of the power supply system when it operates under conditions of increasing distorting loads.

A description of the developed models, algorithms and software for operational assessment of the energy balance on board spacecraft for optoelectronic observation of the Earth’s surface in order to monitor the achievement of the performance targets of a space observation system is given. On the basis of the obtained models and algorithms, a software module was developed for assessing the onboard energy balance in real time, used as part of the software for assessing the target and main design indicators of the space surveillance system. The module’s user interface provides windows for entering and controlling the initial data according to the parameters of the power supply system and cyclograms of connecting on-board system devices, as well as windows for displaying the results of energy balance modeling in digital form and in the form of dynamic diagrams. The use of software based on the proposed models and algorithms makes it possible to more reasonably and quickly develop the initial requirements for the designed onboard systems of remote sensing spacecraft of high-detail and operational observation and to accelerate the process of coordinating design characteristics of the spacecraft at the initial stages of design. The proposed methods, models and software are universal and can be used in the design of Earth remote sensing spacecraft with a wide range of target indicators, target equipment composition and onboard support systems.

Objective When urban rail transit line adopts the continuous co-phase power supply mode, a fault in the traction network may cause extended power outage due to the complexity and non-backup structure of the traction network. Therefore, it is necessary to optimize the segmental power supply scheme for the traction network. Method A segmental power supply scheme for the traction network applicable to the continuous co-phase power supply mode is proposed. Based on the topological characteristics of the segmental power supply of traction network, and combined with the coupling characteristics of vehicle-traction network, the identification methods of segmental short-circuit and neutral section short-circuit are proposed. The control schemes for these two fault scenarios are analyzed, and the self-healing process of the traction network under the above two fault scenarios is described, corresponding circuit breaker control schemes are formulated. In the case study of Guangzhou Metro Line 18, the correctness and reliability of the proposed segmental power supply scheme and the fault identification methods are verified by MATLAB/Simulink software simulation. Result & Conclusion The proposed method can effectively identify faulty segments. The circuit breaker control scheme for the traction network fault can provide reliable main protection for the segments and neutral sections, ensuring stable and efficient operation of the traction power supply system of Guangzhou Metro Line 18.

The Hong Kong - Shenzhen Western Railway is important infrastructure supporting the construction of the Hong Kong-Shenzhen Western Corridor. This study aims to determine the optimal target speed value, focusing on facilitating fast travel for passengers between the two regions, adapting to the technical standards of both regions, and ensuring economic feasibility. The research is significant for improving service quality and maximizing project's economic returns. Comprehensive comparisons of target speeds was conducted using survey methods, experimental methods, and both quantitative and qualitative analysis. First, the technical standards of the Hong Kong rail network and the Greater Bay Area intercity railways were reviewed. An initial range of target speeds was determined based on the functional positioning of the railway. Simulations were then performed to calculate the interval running time for different target speed ranges, analyzing their adaptability to time and station spacing. Comparisons were made from the perspective of train operations. Additionally, the number of facilities, system compatibility, engineering feasibility, and construction investment for different power supply systems were analyzed, leading to recommendations on the optimal power supply system. Further analysis involved calculating the vehicle procurement costs, depot size, construction expenses, and property development revenue associated with different train model platforms, allowing for comparisons of target speeds based on power supply and vehicle model considerations. Based on comprehensive comparisons, the advantages and disadvantages of each target speed were summarized, and a value of 160 km/ h was recommended for this project. The research conclusions comprehensively consider the technical standards, time-space distance, project functionality, power supply systems, vehicle platform, engineering economics and other influencing factors from both Hong Kong and mainland China. This provides strong support for the reasonable determination of the project's target speed and also offers useful references for the selection of target speeds for intercity railways within the Hong Kong - Shenzhen metropolitan area. [ABSTRACT FROM AUTHOR]

The article discusses the application of modern business analytics tools to the analysis of operating modes of an alternating current power supply system, using the example of an electrified section of an AC railway with phase-by-phase measurement of instantaneous voltage and current values obtained from solving a system of differential equations. The analysis of the power supply system’s operating modes is justified by selecting analytical platforms such as Power BI, which has deep integration with Microsoft products, Tableau, known for its powerful data visualization capabilities, and Qlik, which employs an associative data model, allowing users to interact with data without the need to predict analysis methods. The AC railway power supply system under consideration includes traction substations and non-traction loads powered by the "two-wire-rail" (TWR) lines, as well as the external power supply system from which traction substations receive electricity. Based on the obtained instantaneous current values, Matlab՚s computer algebra tools were used to calculate the voltages at the nodes of the power supply system. Power components and integral indicators were calculated in the QlikView environment, which is used for processing a large volume of numerical data and visualizing it. The interactivity of switching between visualizations and the associative data model in QlikView allowed time savings when analyzing large amounts of information in the form of instantaneous voltage and current values obtained by solving hundreds of differential equations using numerical methods. Using a script with Qlik՚s own data processing language enabled the derivation of integral energy characteristics by applying standard data aggregation functions and principles for determining effective values for alternating current circuits. [ABSTRACT FROM AUTHOR]

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The aircraft power supply system is the power source of all electrical equipment on board，thus its safety and reliability are pretty important. Against the backdrop of environmental protection and high-efficiency development needs，research and application of more/all electric aircraft technology with electric power as the core is advanced. The widespread use of electric drive devices and power electronic devices has led to the complexity of aircraft power supply system structure，which puts forward higher requirements for aircraft reliability，safety，testability and maintainability，so that researches on fault diagnosis technology for aircraft power supply systems are of great significance. In this paper，firstly the composition structure and respective functions of aircraft power supply system are introduced. Secondly，the development process of aircraft power supply system is outlined. Thirdly，the characteristics of typical domestic and foreign power supply systems are compared. Fourthly，the main failure modes，fault characteristics and failure causes of aircraft power supply system are summarized，and a design architecture of aircraft power health management system is proposed. Fifthly，the research progress of fault diagnosis methods based on model and data are reviewed，then，the characteristics of various diagnostic methods are evaluated from aspects such as accuracy，data demand，applicability and implementation difficulty. Finally，the challenges and development trends of fault diagnosis technology for aircraft power supply system are pointed out.

In the field of designing power supply systems of open pits an important role is attributed to the problems of components reliability analysis, which can be solved by integrated application of different analysis methods for individual types of electrical equipment and network devices in power supply systems. The purpose of the work is to establish optimal parameters for an open-pit mine power supply at mining and processing complexes, and to conduct research that allows a technical and economic model of the system to be created. It has been established that mathematical statistics provides a number of methods for establishing the homogeneity (or heterogeneity) of the population of random variable values. When analyzing the data of failure statistics of electrical equipment, the method of comparative estimate of two sample averages (compared to the method of comparing the empirical distribution with the normal distribution or the moving average method) is the most acceptable. The paper presents accident rates of electrical equipment of open-pit substations and network devices of the quarry processed on the basis of data, also presents the relationship between the reliability of the circuit and its elements and shows the influence of protection reliability on the reliability of the circuit. Methods of optimizing open-pit power supply systems are presented, which consist in the use of first-order gradient methods, second-order methods or the so-called quadratic optimization methods, and random search methods. A group of gradient methods is the most widespread for solving nonlinear programming problems, among which the method of steepest descent should be considered primarily. The combination of random search with the penalty function method makes it possible to determine conditional extrema for the problem of optimizing the electrical grid and system operation mode. The method of random descent, which consists in determining the minimum of the target function according to an appropriate algorithm, is also considered, in which the direction of motion is generally given by a random vector uniformly distributed over a hyposphere.

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The power supply system being created is intended to provide electricity to spacecraft systems. It ensures that the design characteristics of the solar battery of the prototype are preserved and makes it possible to install means to support the thermal conditions of the photovoltaic battery while maintaining the cost of production of the prototype solar battery. Various types of solar energy concentrators are considered: concentrators in the form of individual convex linear Fresnel lenses, Flexible Array Concentrator Technology concentrators, Stretched Lens Array concentrators. A method for improving the characteristics of the spacecraft solar system is presented. The methodology includes the calculation of various types of concentrators, types of photovoltaic converters and types of solar battery frames. As an example of the implementation of the methodology, the design of solar battery panels was developed. A comparative table of the solar battery before and after modernization is provided.

Objective Most existing studies on catenary system dynamics simulation are based on the assumption that the pantograph base has only longitudinal degrees of freedom, neglecting the influence of carbody vertical vibration induced by wheel-rail excitation on PC (pantograph-catenary) current collection performance. It is necessary to study the vehicle-pantograph-catenary system (hereinafter referred to as VPC) as a whole. Method Models of PC coupling dynamics and VPC multi-body dynamics are established for both rigid and flexible catenary types. Dynamic PC current collection tests are conducted on a case track, and the feasibility of the calculated results of rigid catenary VPC multi-body dynamics model is verified. Based on train speeds of 80 km/h, 90 km/h, 100 km/h, 110 km/h, and 120 km/h, two speed conditions are selected for the analysis of the vertical dynamic responses at the base of rigid catenary pantograph insulator. Comparative analysis of various dynamic response parameters of the pantograph models and VPC models for both catenary types are conducted under the above five speed conditions. Result & Conclusion The simulation calculation results of the established VPC multi-body dynamics model are reasonable. Carbody vibration has a certain influence on the pantograph current collection performance. Under flexible catenary, carbody vertical vibration has little impact on PC current collection performance, thus may be disregarded. Under rigid catenary, compared to the pantograph model without considering carbody vertical vibration, the PC statistically minimum contact pressure and the pantograph-head maximum lifting displacement calculated by the VPC model considering carbody vertical vibration increase with the increase of train operating speed. The maximum change rate of the PC statistically minimum contact pressure is 24.7%, and the maximum change rate of pantograph-head maximum lifting displacement is 4.2%.

The “dual carbon” goals have set forth demands for data centers to be efficient， reliable， and have low carbon emissions. Consequently， a full DC power supply system， incorporating renewable energy sources and large-scale energy storage， was constructed and comprehensively evaluated. Firstly， the characteristics and requirements of each link of “source-network-load-storage” in the power supply system were analyzed. Taking account of system efficiency， availability， economy， and environmental friendliness， an evaluation indicator system was established. Subsequently， a DCES （data center energy system） architecture evaluation tool was developed using the analytic hierarchy process （AHP） and fuzzy comprehensive evaluation method. Finally， through DCES， a comparative evaluation was performed between the full DC power supply system and the conventional AC power supply system. The results indicate that although the proposed full DC power supply system may have slightly inferior economic performance， its overall evaluation indicators are superior， making it a viable option for the future new power supply system in data centers.

[Objective] To address the challenges about renewable energy utilization and significant grid voltage fluctuations in urban rail transit power supply system, a power supply solution based on bidirectional converter technology for traction system is proposed. [Method] The main circuit topology and operational logic of bidirectional converters are introduced. The control characteristics of bidirectional converters under two operating modes of independent power supply and hybrid power supply are presented, and the external characteristic curves combining constant voltage and droop are designed. Using the example of Xuzhou Metro Line 2, tests are conducted for both independent power supply and hybrid power supply under traction and braking conditions for a single train AW0 (unloaded) on the depot test track. Same tests are also performed under normal operation conditions with 12 trains on the mainline. Performance indicators for train operation and bidirectional converters are evaluated. [Result & Conclusion] Bidirectional converters can automatically and smoothly switch between rectification and inversion modes based on the train on-line operation conditions, automatically adapting to the train traction/braking conditions. The use of bidirectional converters in power supply significantly ameliorates train grid voltage fluctuation, preventing working conditions below 1 500 V and enhancing train traction characteristics.

The article presents the classification of fuses, breakers, circuit breakers and packet switches. The laws of change of probabilistic reliability characteristics of the studied devices, as well as low-voltage cable lines are determined. Types of functions of change of basic reliability parameters are determined and corresponding graphical dependences are shown. The comparison of the obtained results of the values of probability of failure-free operation time with the requirements of GOST and passport data is carried out. The investigated probabilistic parameters of lowvoltage devices and cable lines are checked for compliance with the accepted law of distribution of random variables.

In the context of the full-scale Russian invasion and active destruction of critical infrastructure facilities by missiles, guided aerial bombs and kamikaze drones, the task of reliable protection of these facilities is urgent. To solve this problem, various air defence systems, mobile rifle groups, infrastructure defences, electronic warfare systems, etc. are used. However, the high cost of building defences and missiles for air defence, the complex trajectory of enemy objects, which complicates the effective operation of mobile rifle groups, makes the solution to this problem ineffective. To increase the efficiency of critical infrastructure protection, it is proposed to use a multi-agent system based on a swarm of multi-copter drones, which is deployed within a certain object. The agent of this system is planned to use multicopter drones that perform the functions of detecting an enemy object, recognising it, determining its trajectory and movement parameters, and then neutralising it by detonating a cumulative charge in the immediate vicinity of the enemy UAV. To do this, a multiagent system based on intelligent algorithms must develop an automatic decision on which of the drones should move to intercept the enemy UAV and along which trajectory. In order to effectively implement this hypothesis, it is important to choose the right type of multicopter drone. Previous attempts to systematise information have been largely general in nature. A lot of information is in the public domain. Therefore, this work is aimed at analysing the main parameters of existing drones for various purposes in order to select the optimal UAV for use as part of a multi-agent system. his paper reviews the parameters of the main attack drones of the Russian Federation of the Shahed type, their communication and flight control systems. The article analyses FPV drones, which are proposed to be used as a prototype for the future system. The advantages and disadvantages of different types of small UAVs are noted. Adapted versions of the multi-copter drone design developed by scientists of the National University of Chernihiv Polytechnic are presented, which have advantages over commercial analogues in terms of load capacity, power supply, flight time, etc. Particular attention is paid to the power supply systems for multi-rotor UAVs. The features of rechargeable batteries and current trends in the development of semiconductor energy converters used to power drones are considered. After analysing several types of UAVs, it can be concluded that the FPV drone is the most suitable for performing tasks related to the detection and neutralisation of a low-speed aircraft target within the framework of a multi-agent system for the protection of critical infrastructure. The disadvantages of this type of UAV, associated with a small range and operating time, can be partially compensated for by using intelligent algorithms for controlling electric motors and alternately changing the elements of the multi-agent system ‘on duty’. This is made possible by the use of open-source flight controllers. The second significant drawback of such drones is the need for the operator to be close to the target, which creates a certain delay associated with the human factor. Therefore, in this context, UAVs, which are elements of a multi-agent system, should use an advanced information and measurement system that, based on information from various sensors, using intelligent algorithms based on artificial intelligence methods, will make an automatic decision to identify the target, determine the trajectory, intercept and neutralise the drone closer to the target. This will be the focus of further research within the framework of R&D 0123U101819 ‘Multi-agent system for the protection of critical infrastructure facilities based on a swarm of multi-copter drones’ [ABSTRACT FROM AUTHOR]

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Rail transit system plays a pivotal role in the contemporary transportation landscape. In response to the increasing demand for clean and sustainable energy within the transportation sector, the power systems of rail transit vehicles are undergoing a notable evolution characterized by the diversification of types and a commitment to environmentally friendly energy sources. This article systematically examines the historical development of traction power systems for rail vehicles. the current state and future trends in vehicle power system technology, aligning with national energy security imperatives, the green transformation of the transportation energy landscape, and the integration of emerging energy technologies were investigated and analyzed. Against the backdrop of China's national “30·60” dual-carbon target, a SWOT analysis was conductd to evaluate the new energy development direction for China's rail vehicle power systems. By comparing the results, a reference path is delineated for the integration and advancement of China's rail vehicle power systems and new energy. Three key aspects are addressed in a specific proposal, encompassing low-carbon and clean energy supply, modernization, and energy efficiency. To guide relevant technical research and policy formulation, the article outlines the future development trends of rail vehicle power systems in three main dimensions: low-carbon and clean energy supply, energy storage, and modernization with a focus on energy conservation. This comprehensive analysis aims to contribute valuable insights and support for future endeavors in the realm of rail transit power system technology and sustainable energy policies. [ABSTRACT FROM AUTHOR]

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RELEVANCE: The possibility of a reasonable choice of an alternative strategy for the organization of maintenance and repair (M&R) of the power company's equipment is a guarantee of the successful implementation of its strategic priorities. The tasks in this direction are quite relevant.PURPOSE: To develop a unified methodology that, from the general standpoint of a risk-based approach, would allow comparing two alternative strategies for managing the assets of an energy company "by periodicity, operating time" and "by technical condition", according to a set of key criteria for the effectiveness of M&R.METHODS: When solving problems, methods of forming and adjusting schedules for repairs of electrical equipment, calculating reliability and probabilities of failure in the power supply system of consumers, taking into account its circuit features, assessing the technical condition of equipment according to non-destructive testing and diagnostics, comparing the costs of maintaining and restoring reliability and damages from its violations were used.RESULTS: A risk-oriented methodology has been developed and verified, which makes it possible to evaluate and select the optimal equipment maintenance strategy for the energy company according to uniform efficiency criteria. An algorithmic implementation of the developed methodology is obtained, which is the basis of a computing complex for choosing and making decisions. The verification of the methodology and algorithm is carried out on the example of a real object – a power supply system for oil production consumers using reliable operational and diagnostic information.CONCLUSION: The results obtained fully compensate for the lack of methodological possibilities in comparing two basic alternative strategies for electrical equipment maintenance based on a single risk-based approach. The developed methodology is a unified decision-making tool at the stage of alternative analysis. The illustration of the methodology by a real numerical example demonstrates the consistency of the solutions obtained with the results of expert assessments and operational experience.

Thе prоspеcts fоr thе аpplіcаtіоn оf thе Smаrt Grіd cоncеpt аs оnе оf thе mаіn dіrеctіоns оf thе dеvеlоpmеnt оf thе еlеctrіc pоwеr іndustry аrе cоnsіdеrеd. Thе аdvаntаgеs оf thе іmplеmеntаtіоn оf thе Smаrt Grіd cоncеpt аіmеd аt еnsurіng thе rеlіаbіlіty аnd еnеrgy еffіcіеncy оf еlеctrіcіty supply, іmprоvіng thе quаlіty оf еlеctrіcаl еnеrgy, thе thrоughput оf еlеctrіcаl nеtwоrks, thе оrgаnіzаtіоn оf pаrаmеtеr mоnіtоrіng, cоntrоl оf thе stаtе оf thе еnеrgy systеm, аnd thе іntеgrаtіоn оf rеnеwаblе еnеrgy sоurcеs hаvе bееn іdеntіfіеd. Thе tоpоlоgy оf thе Smаrt Grіd nеtwоrk wаs studіеd wіth thе pоssіbіlіty оf cоnnеctіng еnеrgy аccumulаtоrs thаt crеаtе а bіdіrеctіоnаl еnеrgy flоw іn thе systеm, wіth thе prоvіsіоn оf rеgulаtіоn оf іts dеnsіty dеpеndіng оn thе dеmаnd fоr еlеctrіcіty аt thе currеnt mоmеnt іn tіmе. Thе pаrаmеtеrs оf thе іntеllіgеnt nеtwоrk systеm wіth thе usе оf еnеrgy аccumulаtоrs аrе оbtаіnеd оn thе еxаmplе оf thе trаctіоn pоwеr supply оf еlеctrіc rоllіng stоck, tаkіng іntо аccоunt thе еlеctrіcіty cоnsumptіоn by trаіns аnd thе аccumulаtоr chаrgе stаtе. Thе gіvеn cаlculаtіоn rеsults mаkе іt pоssіblе tо stаtе thаt thе usе оf еnеrgy аccumulаtоrs іn thе Smаrt Grіd nеtwоrk іncrеаsеs thе аmоunt оf еnеrgy rеturnеd tо thе еlеctrіc pоwеr supply nеtwоrk, аs а rеsult оf whіch thе оvеrаll systеm cоsts аrе rеducеd. Ref.10, figure, table.

The possibility of using neural networks in the field of the energy coefficients correction of a power supply system with uneven load in phases is being studied. This need is justified by the fact, that the calculation of the necessary parameters of the symmetry-compensating device was previously based on the Nelder – Mead search optimization method. Search optimization performing is computationally expensive, takes long computation times, and may calculate anomalous values. The article develops the idea of using technology for predicting the parameters of a symmetry-compensating device, based on neural network modeling using Bayesian regularization. For a given set of initial data, the best selected configuration turned out to be a neural network of two layers, implemented in the MATLAB package using the machine learning tool Neural Network Toolbox. The network input parameters are a set of tuples, consisting of load values in each of the three phases of the power supply system, which are resistive-inductive in nature. There are six input quantities in total (load resistance and inductance values in each of the three phases) and all their values are different, which causes current asymmetry in the network and reactive power. The target matrix is formed from tuples, consisting of three values, which are the parameters of the symmetrical compensating device, calculated by the optimization method, in such a way as to compensate reactive power and to balance currents in the network. The number of data tuples, required to train a neural network was determined empirically. During the experiments, the optimal number of neurons in the neural network was also revealed. The use of the generated neural network to calculate the parameters of the symmetry-compensating device determined approximate solutions is comparable in accuracy to the values, found by optimization methods. With the help of the generated neural system, adequate quasi-solutions for calculating the parameters of the symmetry-compensating device were determined, which, in case of calculation, using the optimization method, led to anomalous values, that didn’t optimize the energy coefficients of the power supply system to the required extent. Also, such neuropredictions protect the system from receiving excessive high parameters of symmetry compensating device, which can be obtained with an optimization approach.

The article describes the process of creating a BS simulation model. The object of the study is the BS, which is part of the STAGE of a spacecraft placed in a highly elliptical orbit of an artificial Earth satellite. When creating a simulation model, the BS was formed by photovoltaic devices (PV) made of helium arsenide (AG), the efficiency of which is 27 %. When creating the simulation model, the following parameters were taken into account: the no- load voltage of the illuminated BS, at a steady temperature when the spacecraft leaves the Earth's shadow of the maximum duration with a deviation of the normal to the surface of the BS from the direction to the Sun, as well as a change in the output current. Also, when creating the model, the effects of external factors are taken into account, such as: a decrease in external atmospheric pressure, changes in the temperature of the BS during the passage of the spacecraft shadow sections of the orbit, ionizing radiation of the KP during interaction with magnetospheric plasma, shadowing by spacecraft structures, and others.

In conditions of constant growth in the cost of traditional oil products and their shortage, the issue of using alternative fuels becomes urgent. The purpose of the article is to identify ways of using alternative types of fuel for the operation of diesel engines. Research methods – analysis and verification of data obtained from scientific publications, which are part of the world-famous scient metric databases, for the relevance of the subject of research. The research results reveal the advantages and disadvantages of dual-fuel engines operating on gaseous fuel with diesel fuel additive, the impact of this type of engine on emissions and toxicity of exhaust gases, in particular nitrogen oxides NOx. The application of the so-called gas nozzle and the cross-section of the holes of its nozzles are substantiated. It was analysed and established that the most economically expedient is the use of liquefied petroleum gas for the operation of diesel engines by implementing the gas-liquid cycle; it was found that the most promising for this is gas cylinder equipment of the so-called 4th generation. A retrospective analysis of studies of internal combustion engines with gas cylinder equipment showed an increase in motor resource when using gaseous fuels, as well as the negative side of using gaseous fuels, which consists in reduced power when converting carburettor engines, however, the use of these fuels for the operation of diesel engines completely eliminates this disadvantage. Based on the research analysis, the influence of the ignition dose, when the engine is operating on the gas-diesel cycle, on the performance at different loads was also established, and a recommendation was found to switch to the diesel cycle from the gas-diesel cycle at loads less than 30% of the nominal one. The optimal scheme for the implementation of the gas-diesel cycle, which is relevant and promising for more widespread energy and transport vehicles, has been substantiated and selected. Based on the analysed schemes, it was established that the scheme that can be taken as a basis for further research in this direction is the scheme of the DG-Flex BOSCH gas-diesel system. The practical value of the work lies in the justification of complex conversion with partial replacement of diesel fuel with liquefied petroleum gas as the most rational way of converting serial diesel engines into dual-fuel engines

The article describes the method of synthesis of the simulation model of pulse converters with the control system, intended for implementation in FPGA. The technique is based on the structural representation of integro-differential and algebraic equations and the method of switching breaking functions. The models you develop allow you to bring modeling time closer to real. The method is described by an example of a solar battery energy conversion channel of an automatic spacecraft power supply system. The paper considers the possibility of implementing a solar-hydrogen energy supply scheme. This concept involves the accumulation of excess energy in the form of chemical energy on board the spacecraft. [ABSTRACT FROM AUTHOR]

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Modern vehicles have increasing safety requirements and a need for reliable low-voltage power supply in their on-board power supply systems. Understanding the causes and probabilities of failures in a 12 V power supply is crucial. Field analyses of aged and failed 12 V lead batteries can provide valuable insights regarding this topic. In a previous study, non-invasive electrical testing was used to objectively determine the reasons for failure and the lifetime of individual batteries. By identifying all of the potential failure mechanisms, the Latin hypercube sampling method was found to effectively reduce the required sample size. To ensure sufficient confidence in validating diagnostic algorithms and calculating time-dependent failure rates, all identified aging phenomena must be considered. This study presents a probability distribution of the failure mechanisms that occur in the field, as well as provides insights into potential opportunities, but it also challenges diagnostic approaches for current and future vehicles. [ABSTRACT FROM AUTHOR]

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