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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]

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.

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.

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.

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.

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.

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]

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]

The object of research is the processes of intelligent management of the computer environment of data objects of the critical infrastructure of railway transport. When developing an innovative model of deep mutual integration of the architecture of an intelligent computer environment for the management of objects in the power supply system of railway transport, the only urgent task is to solve the problems of efficient and reliable power supply of electricity for train traction to ensure the transportation process. The approaches, mathematical models and methods that became the basis for the creation of an innovative model and a new structure of the management system, the integration of the architecture of the computer environment of data of critical objects of the infrastructure of railway transport, meet the requirements of modernity and the strategy of sustainable development of the transport infrastructure. Management of an intelligent computer environment in the context of the railway power supply system is a complex process that includes the use of various technologies and strategies to optimize the functioning of systems, increase reliability, ensure efficient use of electricity, and ensure the transportation process. The basis of the creation of an intelligent computer environment is the principle of a single informational and synchronous space for the formation of primary information, which is an important concept in the development of intelligent control systems for the power supply system of railway transport. This principle requires that all parameters and data that are collected from different systems of power supply facilities should be combined in a single information space and be available for analysis and management in real time. This principle creates the basis for innovative solutions in the field of railway power supply system management, and the use of the Internet of Things, artificial intelligence, machine learning and deep learning allows the development of systems that meet modern requirements for the efficiency and reliability of energy systems. The use of the approach of deep mutual integration of the architecture of the computer environment is key in the possibility of automating the processes of data collection and analysis, as well as in improving the interaction between the components of the systems of power supply facilities of railway transport, the reliability and efficiency of the system, which makes it more flexible and adaptive to changes in load and working conditions. The research presented in the work can be used in practice in organizations, structural units and at the levels of the management system of critical infrastructure objects in railway transport, transport sector enterprises, which will allow a quick response to an emergency situation and switch to backup modes, ensuring reliability and availability of power supply in conditions of challenges. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The AC electric arc furnace (EAF) is becoming a core apparatus of the modern steel industry. Nevertheless, it used to be a major threat of power quality in the traditional power supply system. In this paper, a flexible power supply system of the AC EAF is proposed, which is expected to completely alter its inherent cognition of impact load in the power grid. The basics of the power supply for EAF are first reviewed and the novel techniques to enhance the operation flexibility of EAF are introduced. The power circuit and the control structure are then presented, followed by the detailed strategies of various operations fully considering the features of EAF. A large disturbance stability criterion based on the mixed potential theory is also established for the practical application. Both electromagnetic transient simulations using PSCAD and benefit analyses verify the feasibility of the proposed system.

THE PURPOSE. To examine the features of the location and the overall structure of theSredne-Kamchatskyisolated power hub. To considerthe structure of installed electric capacity and the composition of generating equipment of power plants in the mentioned power hub. To determine the composition and characteristics of the electric grid economy. To analyze and determine the main indicators of electricity consumption and capacity dynamics of the hub. To perform an analysis of the existing balance of power and electric energy, to determine the main technical and economic parameters of the power supply. To consider options for the power supply system development including on the basis of renewable energy sources. METHODS. When solving this problem, we usedmethods of mathematical processing of statistical data and methods of normative forecasting. RESULTS. We considered the special featuresof generating capacities and network infrastructure development,the issues ensuring the long-term and medium-term demand for electric energy and capacity, the formation of stable and favorable conditions for attracting investment in the construction of electric power facilities.The study calculated the current and prospective balances of electricity and capacity in the discussed power hubbased on the analysis of the energy structure of an isolated power unit and the dynamics of electricity consumption. CONCLUSION. Any failure in an isolated system leads to dangerous crisis phenomena and significant economic losses. Thus it is important to provide reliable and efficient power supply to energy isolated territories. The presented comprehensive assessment of the state of the electric power industry in the isolated Sredne-Kamchatsky power plant allows us to predict the prospects for its development within the framework of the overall development of the electric power complex of the Kamchatka Territory.

Problem. The article analyzes the design features of the systems and components of the Tesla Model S electric car, which allows choosing the initial characteristics for the mathematical model of the acceleration dynamics of the electric car, determines the cost characteristics of its power plant (electric motor) and battery. Goal. The purpose of the work is to determine the initial characteristics of the systems and components of a modern electric vehicle for their further use in a mathematical model of the acceleration dynamics of an electric vehicle. Methodology. The approaches adopted in the work to achieve the set goal include understanding the peculiarities of the initial characteristics of the systems and components of electric vehicles, which are the world leaders in the market of such vehicles. Results. In the work, a comparative analysis of the layout schemes for the implementation of transmissions in the designs of modern electric vehicles, the characteristics of their power plants (electric motors), the characteristics of energy converters (inventories), and the features of the power plant power plant of a modern electric car are determined. Originality. The conducted analysis of the design features of systems and components of the Tesla Model S electric car made it possible to form a general idea about the features of the implementation of work processes in the electric drive of an electric car, which can be used as initial parameters or characteristics during the simulation of the acceleration dynamics of an electric car. Practical value. The obtained results make it possible to formulate recommendations for the use of the characteristics of the systems and components of the electric vehicle during the simulation of the dynamics of its acceleration and to determine the energy consumption in the power system of its traction electric drive.

Electric power supply system planning is practically an important function of the modern light rail transit system with catenary free operation and rapid charging. Installing a modern dynamic load of the traction power supply system with the local electric distribution network needs to consider its capacity and feeder to support enough and efficiently. In this paper, the design of the electrical power supply system of the pilot project of Nakhon Ratchasima Green Line light rail system with 11.6-km line length and 21 passenger stations operated with catenary-free and powered with an on-board energy storage device has been proposed and planned to replace the old local transportation. The traction power supply of the light rail system drawn power from the MV distribution feeder practically consist of receiving power substation, MV power feeding system power feeder substation, charging power supply and service power supply have been designed provided the configuration circuit. A rapid charge system to delivery high power to fulfill the on-board energy storage is considered to recharge at passenger stations with an overhead conductor or wireless power transfer during a short dwell time. A number of charging station is determined accordingly the capacity of the power substation and its positions. The traction power drawn by a train service round-trip that related to the capacity of the power substation as a charging station has been calculated by the simulation of the train movement. The regenerative braking energy during train operated in braking mode is also considered as a partial charging energy the on-board energy storage device. From the proposed design, the motive energy consumption of each scenario charging formations obtains the maximum charging energy drawn by the train between charging points, the capacity of on-board energy storage devices, maximum charging power and the total charging points.

During the current crisis caused by the COVID-19 pandemic, Wearable IoT (WIoT) health devices have become essential resources for remote monitoring of the main physiological signs affected by this disease. As well as sensors, microprocessor, and wireless communication elements are widely studied, the power supply unit has the same importance for the WIoT technology, since the autonomy of the system between recharges is of great importance. This letter presents the design of the power supply system of a WIoT device capable of monitoring oxygen saturation and body temperature, sending the collected data to an IoT platform. The supply system is based on a three-stage block consisting of a rechargeable battery, battery charge controller, and dc voltage converter. The power supply system is designed and implemented as a prototype in order to test performance and efficiency. The results show that the designed block provides a stable supply voltage avoiding energy losses, which makes it an efficient and rapidly developing system. [ABSTRACT FROM AUTHOR]

Electrical power is essential in human life. Thus, the security and reliability of its supply are of critical importance in a country's industrial and economic development. The leakage and improper use of electricity may cause serious problems such as fire and electrocution. To prevent such incidents and minimize the loss of life and property, a leakage current detector and warning system are developed in this study. With a high-precision current transformer and high-gain linear converter, the detector effectively detects leakage current over 1 mA, which is validated in different methods. The detector can be integrated into widely used electric meters (Taipower Datong's sub-meter model D4S) easily, and information on detected leakage current is transmitted to the cloud server through narrowband IoT wireless communication (NB-IoT) to warn users and management personnel of the electrical power line. The proposed detector and system are expected to prevent the fire caused by leakage current which was the main cause of the fire at homes and buildings and can be an effective means to manage the electrical powerline system and metering facilities. [ABSTRACT FROM AUTHOR]

A method of forecasting the balance of electricity consumption of urban development objects, civil purposes using discrete macromodels is proposed. We consider the power supply system (PSS) of the district, which is characterised by power supply from general-purpose power grids, as well as having its own generation of electricity from renewable energy sources (RES). Such a local electric power system (LES) under certain conditions can be operated as an independent balanced electrical facility. For optimal operation of the LES under these conditions, it is necessary to predict its power consumption schedules. The proposed macromodelling method allows to develop deterministic models of power consumption with the required accuracy on the basis of retrospective information without the use of data preprocessing procedures. The solution to the problem of forecasting electricity consumption schedules is simplified by using only basic or deterministic characteristics in the construction of the model. These include fractal properties of PSS load schedules.

High-power turbine generators are needed in logging-while-drilling systems to supply power to the downhole instruments. The current high-power power supply system employs a rectifier-voltage regulator, and the rectified direct-current (DC) voltage increases with the mud flow rate. Moreover, as voltage regulator modules operate in limited ranges, various impellers and guide wheel combinations are generally used to generate electronic power. In practice, it is necessary to adjust different impeller and guide wheel combinations according to the mud pump discharge rate at the operation well site to change the flow rate of the mud on the impeller to meet the voltage range requirements of the DC conversion module. This study uses theoretical analysis and simulation calculations, applies a proportional–integral–differential closed-loop control model, and completes the design of a power supply system modulated and stabilized using pulse-width modulation (PWM). Moreover, the study involves analyzing its active-control rectification characteristics, conversion efficiency, and load-adjustment response time with an alternating-current (AC) voltage input of 60–150 Vms. The results suggest that the regulated power supply system can achieve active rectification over various AC inputs, ensuring that the bus voltage always meets the design requirements with high efficiency and satisfactory load adaptability. Therefore, a set of impeller and guide wheel combination based on this stabilized, modulated power supply system can be achieved to meet the operational needs of various AC power inputs under different mud flow ranges, improve applicability in different working wells. [ABSTRACT FROM AUTHOR]

PURPOSE. To consider aspects of solving the complex problem of reasonable choice and assignment of the repair management strategy for the equipment of power supply systems of oil production consumers according to the actual technical condition. To form a methodology for assessing the comparative effectiveness of repair management strategies: «By frequency, running hours» and «By technical condition». To verify the performance of the integrated methodology. Justify and demonstrate the effectiveness of the repair management strategy: «By technical condition» of the equipment on the real example of the typical scheme of the electrical supply system of oil fields.METHODS. In solving the problems set: the method of block diagrams for calculating the structural reliability of electric distribution network, including the probabilities of power supply failure in the circuit of each technological consumer, taking into account the possibility of redundancy and imposing an emergency restoration of the main element on the planned repair of the reserve, the method of hierarchy analysis for integral assessment of the actual technical condition of electrical equipment 6 (10) kV, method of calculating the mathematical expectation of damage from technological losses of oil production to assess the severity of the consequences of disruption of electricity supply to consumers of oil production, the method of expert decisions to adjust the regulatory periodicity and frequency of scheduled repairs of equipment, depending on the actual value of technical condition index.RESULTS. The relevance of the research direction is substantiated. Computational methodology of comprehensive assessment of comparative efficiency of equipment repair management strategies in oilfield power supply system «By frequency, running hours» and «By technical condition» to justify the priority of one of them has been formed. On a concrete computational example the preference of strategy choice «By technical condition» is proved as applied to the equipment of 6(10) kV power supply systems of oil fields.CONCLUSION. The developed methodology and its validation on the example of a real power supply system allows to substantiate and illustrate the effectiveness of the strategy «By technical condition» in comparison with the strategy: «By frequency, running hours» in relation to the management of repairs of oil production facilities.

THE PURPOSE. The main purpose of the study is to develop the calculation algorithm of energy efficiency indicators. To develop an algorithm, it is necessary to consider the features of the power supply system of the oil and gas production enterprise. Then, the power and electricity balance calculation algorithm should be designed to evaluate the share of the technological processes’ consumption, analyze losses, and determine the source of imbalance. The assessment of energy efficiency indicators will require adaptation of the parameter’s identification method for rotating electrical machines in operating modes. To calculate the specific equipment energy, it is necessary to use power tracing in the algorithm. The final stage is to develop a visualization of a software prototype for monitoring and control energy efficiency indicators of an oil and gas production enterprise.METHODS. The equipment parameters identification method based on actual measurements is used for designing a mathematical model. To calculate the steady-state, the nodal-voltage method is used in couple with an addressing matrix for tracing power flows.RESULTS. The paper proposes an algorithm for calculating energy efficiency indicators of equipment for an oil and gas production enterprise. The algorithm is based on the processing and analysis of actual data from the electricity metering devices installed at the enterprise. Analysis of the power consumption information together with the oil production indicators will reveal the most efficient operating mode of the equipment. The calculating algorithm for the specific electricity consumption is considered in the example of a typical hierarchy of metering devices at a field. Further, the paper discusses the possibility of applying the targeting flow distribution principle for reducing power losses. A parameters identification technique is presented for multi equipment nodes to assess energy efficiency and monitor operating parameters.CONCLUSION. The algorithm considered in the paper was introduced into the information system of the production control center at the field as an additional module for assessing energy efficiency. The large deviation of the indicator's values from the specified ones is messaging about the equipment's normal mode violations. It allows creating an optimal schedule of organizational and technical measures to regulate energy consumption and improve the energy efficiency of the enterprise.

The research fields in the fields of information science and computer are very extensive, and there are many research hotspots. Intelligent optimization algorithm is one of the research hotspots. One of the key issues found in research papers in this field is how to effectively improve the search quality of intelligent optimization algorithms in a complex work environment. As a multi-functional swarm algorithm, particle swarm optimization has relatively few parameters, good convergence, and relatively fast working speed. It is a popular intelligent algorithm. In the process of studying the optimal operation of the combined cooling, heating and power system, in order to better dispatch the output of each device in the combined cooling, heating and power system, a combination of chaotic search based on Tent mapping and nonlinear adaptive particle swarm optimization is proposed Optimization algorithm. Taking the operating cost, pollutant emission and energy efficiency of the cogeneration system as the goals, a multi-objective optimization model was established. The simulation results show that the proposed cooling, heating and power cogeneration system optimization method can effectively improve economic benefits, reduce pollution emissions, and improve energy utilization. The traditional model cannot accurately analyze the environmental pollution mitigation effect. In order to avoid this problem, a modeling analysis of the impact of wind power photovoltaic clean energy on the mitigation of environmental pollution is proposed, thereby building a wind power photovoltaic clean energy organization structure and maintaining the application of wind power photovoltaic clean energy the stability of the range. Set wind power photovoltaic clean energy to alleviate environmental pollution factors, and determine the degree of environmental pollution limited by natural numbers under continuous use of polynomial constraints.

One of the main factors for the effective functioning of the power supply system in highly productive coal mines is the uninterrupted power supply of underground consumers for the entire process cycle at sufficient amount of electric energy at a high level of quality and performance. The analysis of electric energy consumption in highly productive coal mine has shown that about 57 % of electric energy consumers are located in underground workings. Consumers can be divided into the following areas of basic technological process of coal production: production areas (13 %); conveyor transport areas (13 %); preparation areas (8 %), and areas of auxiliary processes of coal production: mine drainage (23 %). The increase in the share of controlled-velocity electric drives in the total power balance of fully-mechanized longwalls leads to factors previously atypical of underground power networks. Such factors include changes to the harmonic composition of the network, arising higher current and voltage harmonics, affecting the supplying network and causing heating of electrical equipment, power and electric energy losses. Therefore, the most pressing issues are to improve electric energy quality in underground electric networks of highly productive coal mines. The study has developed a technique for experimental investigations of quality indicators of electric energy (presented in the form of algorithm) in respect to specific conditions of highly productive coal mines. These include dangerous facilities in terms of sudden gas/dust outbursts. This technique was tested at a number of coal mines of JSC SUEK-Kuzbass. The study also presents the results of experimental investigations to determine the actual level of total harmonic distortion (factor) in underground electric networks of fully-mechanized longwalls of coal mines. Of greater importance is justification of higher harmonic filter parameters. To this end a calculation algorithm based on the developed technique has been proposed. Research has shown that application of forward and inverse Clarke transformations for calculating the harmonic filter parameters is applicable for all voltage levels. The simulation model of power supply system of a coal mine fully-mechanized longwall allows conditions of higher harmonics damping to be studied by means of a device for improvement of electric energy quality. Applying the proposed technical solutions to improve the quality of electric energy based on the simulation modeling allowed the successful damping of higher harmonics to be achieved. For example, the total harmonic components voltage (THD (U)) was reduced from 9.07 to 1.77 %.

After analyzing the results of physical tests of the power supply system of the plant, it is found that the values of individual harmonic components exceed the values established by GOST-32144 2013. Based on the data obtained, a simulation model is formed and an analysis of higher harmonics is performed using the packet wavelet transform method. The aim of the work is the analysis and calculation of higher harmonics and additional losses from them in the neutral conductor based on the packet wavelet transform method. The simulation is carried out using the Simulink software package. As a result of the study, it is found that the packet wavelet transform with high accuracy allows to determine the presence of higher harmonics in the power supply system, the efficiency of using the wavelet transform to calculate additional losses in the neutral conductor is shown.

In this work, a self-powered system based on a triboelectric-electromagnetic hybrid pipeline energy harvesting module is demonstrated. Rabbit fur and poly tetra fluoroethylene (PTFE) are used as triboelectric electrodes to fabricate disk-type soft-contact triboelectric nanogenerators (TENGs) instead of traditional direct-contact TENGs to collect the mechanical energy of water flow and convert it into electrical energy. This design has a stable electrical output and gives an improved durability. Its simple fabrication process enables excellent potential for practical applications in industry. In addition, the hybridization of electromagnetic generator module and TENGs module to form a triboelectric-electromagnetic hybrid nanogenerator (TEHNG) can improve the electrical output performance, especially the current output. TEHNG cannot only power small electronic devices, such as lighting systems, but also collect independent fluid energy and monitor data signals simultaneously in harsh environments, such as fluid energy harvesting in industrial production pipelines and temperature and humidity in fluid environments. This work provides an efficient strategy to harvest multiple energies simultaneously, significantly increasing the yield and promoting the application of TENGs in engineering. [ABSTRACT FROM AUTHOR]

Copyright of Eurasian Physical Technical Journal is the property of E.A. Buketov Karaganda University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To lower maintenance costs and improve a metro company's competitiveness, this research came up with an innovative technique using a considering sensitivity and analytic hierarchy process (CSAHP). Along with interviews with managers and workers at the Taipei Rapid Transit Corporation, this study was able to undertake quantitative analysis. To determine which subsystems and metro lines should be prioritized for outsourcing based on the CSAHP framework, we used the criterium decision plus (CDP) program. This research adds to the existing body of knowledge by advancing the existing analytic hierarchy process (AHP) technique and recommending the CSAHP strategy for assessment. According to the findings, the power supply system was the most in need of outsourcing, followed by air conditioning, firefighting, and elevator systems. When considering which of the four metro lines to outsource first, the blue line came out on top, followed by the red, green, and brown lines. By prioritizing the outsourcing of the power supply system as a result of this research, the Taipei Rapid Transit Corporation may cut the system's maintenance expenditures from USD 1.57 million to USD 1.33 million, saving 15% on maintenance costs. Applying these findings can improve the economic benefits of outsourced maintenance for the Taipei Rapid Transit Corporation. [ABSTRACT FROM AUTHOR]

The purpose of this work is the analysis of the power supply system of unmanned aerial vehicle. One of the most important tasks of this system is to ensure the smallest possible losses in order to achieve greater endurance of the aircraft, which means – the ability to complete the mission. The presence of an inactive component of consumed power obviously reduces the efficiency of the entire unmanned aerial vehicle. Considering also that due to the influence of wind, speed changes and other factors, the power system spends a significant amount of time in the transition mode, the impact of this phenomenon becomes even more significant. Thus, the phenomenon of the occurrence of exchange power in the power supply system of an unmanned aerial vehicle is analyzed. One of the most common solutions for unmanned aerial vehicles is the use of a BLDC motor, which is a further development of DC motors and was created with the aim of improving their basic characteristics. This type of engine has gained its popularity due to numerous advantages: high reliability, efficiency, speed and others. The principles of control of the BLDС engine are given. The unmanned aerial vehicle power supply system, built on the basis of a buck converter and a bridge inverter, was analyzed. An equivalent circuit of the converter is built, taking into account the losses in the electric circuit. On its basis the relations for determining the value of exchange power in the power supply system are derived. With the help of these expressions, it is possible to determine the value of the exchange energy at an arbitrary time interval in the real power supply system of the aircraft. A model of the power supply system of an unmanned aerial vehicle with a BLDC engine was built in the Matlab Simulink software environment. A time diagram is obtained, on the basis of which it is possible to draw a conclusion about the content of exchange power in the converter circuit. To minimize this phenomenon, it is necessary to develop a compensation system or an intelligent control system. [ABSTRACT FROM AUTHOR]

The technological installations' characteristics are possible to improve by equipping fans with a frequency-controlled electric drive. However, it can lead to an electromagnetic compatibility problem in the electrical supply system. This problem becomes worse if a large number of fans are included in the technological installation and the electric drives are powered from a substation connected to a limited power source. As an example, in this article we investigate the power supply system of a gas cooling unit with variable-frequency electric drives for fans. The electric drives' operating mode dependences characterizing the non-sinusoidal voltages and currents of the power source are obtained with the help of simulation modeling in the MATLAB environment with the Simulink expansion package. The typical substation circuit usage for the power supply of a group of fans with a frequency-controlled drive does not meet the requirements of IEEE Standard 519-2014. We can solve the problem of electromagnetic compatibility by changing the substation topology and organizing DC busbars and replacing frequency converters with inverters. We proposed forming DC busbars using 12-pulse rectifiers powered by transformers with two secondary windings with different connection schemes. The simulation results confirmed that the proposed substation topology provides the voltage and current harmonics level on the substation power busbars in accordance with the IEEE Standard 519-2014 requirements over the entire frequency range of the fans' motor control. [ABSTRACT FROM AUTHOR]

With the rapid development of more-electric and all-electric aircraft, the role of power supply systems in aircraft is becoming increasingly prominent. However, due to the complex coupling within the power supply system, a fault in one component often leads to parameter abnormalities in multiple components within the system, which are termed associated faults. Compared with conventional faults, the diagnosis of associated faults is difficult because the fault source is hard to trace and the fault mode is difficult to identify accurately. To this end, this paper proposes a graph-matching approach for the associated fault diagnosis of power supply systems based on a deep residual shrinkage network. The core of the proposed approach involves supplementing the incomplete prior fault knowledge with monitoring data to obtain a complete cluster of associated fault graphs. The association graph model of the power supply system is first constructed based on a topology with characteristic signal propagation and the associated measurements of typical components. Furthermore, fault propagation paths are backtracked based on the Warshall algorithm, and abnormal components are set to update and enhance the association relationship, establishing a complete cluster of typical associated fault mode graphs and realizing the organic combination and structured storage of knowledge and data. Finally, a deep residual shrinkage network is used to diagnose the associated faults via graph matching between the current state graph and the historical graph cluster. The comparative experiments conducted on the simulation model of an aircraft power supply system demonstrate that the proposed method can achieve high-precision associated fault diagnosis, even under circumstances where there are an insufficient number of samples and missing parameters. [ABSTRACT FROM AUTHOR]

The article presents information on optimization of steady state regimes in power supply systems in order to minimize power losses. The following tasks were formulated and solved: engine parameters were determined; the steady state of the power supply system was calculated. Statistical characteristics of power losses in asynchronous and synchronous motors and transformers were obtained. Investigations have been carried out for the ore mining and processing enterprise. On the basis of the obtained universal model, a software package has been designed to perform computational and experimental research in order to obtain static characteristics of power losses and loads in the power supply system and to determine the character of variation of these characteristics.

Continuously growing tariff rates for energy carriers required to generate electrical and thermal energy bring about the need to search for alternatives. Such alternatives are intended for the reduction in the electricity and heat net costs as well as the expenses for the operation and maintenance of system elements and damage from power outages or deteriorated power quality. A way to reduce electricity and heat costs is the introduction of distributed energy resources capable of operating on both conventional (natural gas) and alternative (solar and wind energy, biomass, etc.) fuels. The problem of reducing electricity and, in some cases, heat costs are solved by applying mathematical optimization techniques adapted to a specific element or system of the industry in question. When it comes to power industry facilities, optimization, as a rule, includes reducing active power losses by controlling the system mode or specific power unit parameters; planning generating equipment operating modes; defining the optimal equipment composition; improving the regime and structural reliability of grids; scheduling preventive maintenance of equipment; searching for effective power unit operating modes. Many of the problems listed are solved using direct enumeration techniques; modern technical tools allow quickly solving such local problems with a large number of source data. However, in the case of integrated control over the power system or its individual elements, optimization techniques are used that allow considering a lot of operating limitations and the target function multicriteriality. This paper provides an analytical review of optimization techniques adapted to solving problems of improving the efficiency of the power facility operating modes. The article is made on the basis of the research conducted by the authors in the area of optimization of operating modes for electric energy systems and grids. The authors drew conclusions on the applicability of mathematical optimization methods in the power energy area. While conducting the research, the authors relied on their expertise in the development and introduction of the method to optimize the operation modes of energy supply systems with heterogeneous energy sources. [ABSTRACT FROM AUTHOR]

The electric unmanned aerial vehicles (UAVs) are rapidly growing due to their abilities to perform some difficult or dangerous tasks as well as many public services including real-time monitoring, wireless coverage, search and rescue, wildlife surveys, and precision agriculture. However, the electrochemical power supply system of UAV is a critical issue in terms of its energy/power densities and lifetime for service endurance. In this paper, the current power supply systems used in UAVs are comprehensively reviewed and analyzed on the existing power configurations and the energy management systems. It is identified that a single type of electrochemical power source is not enough to support a UAV to achieve a long-haul flight; hence, a hybrid power system architecture is necessary. To make use of the advantages of each type of power source to increase the endurance and achieve good performance of the UAVs, the hybrid systems containing two or three types of power sources (fuel cell, battery, solar cell, and supercapacitor,) have to be developed. In this regard, the selection of an appropriate hybrid power structure with the optimized energy management system is critical for the efficient operation of a UAV. It is found that the data-driven models with artificial intelligence (AI) are promising in intelligent energy management. This paper can provide insights and guidelines for future research and development into the design and fabrication of the advanced UAV power systems.

THE PURPOSE. To analyze scenarios for the development of the energy complex of one of the regions of the North-East of Russia for the period up to 2030 with a target vision until 2050. This will require an analysis of the current state of the energy complex; show the latest changes in the power supply system; propose promising areas for the transfer of electricity. METHODS. To assess the current state of the electric power industry, from the point of view of the most efficient use of natural energy resources and the potential of the energy sector of the economy, methods of collecting and processing statistical data were applied. For the technical assessment of the state of electric power facilities, analytical and logical- probabilistic methods for determining reliability were applied. To predict energy consumption, mathematical modeling methods were used with the construction of approximating polynomials. RESULTS. The article evaluates the strategic and moderate scenarios for the development of the energy sector of the Republic of Sakha (Yakutia) in modern conditions, taking into account the increase in the energy efficiency of the region's economy. The indicators of electricity consumption throughout the republic, the Western Energy District and the decentralized power supply zone were subject to assessment. Long-term forecasts made do not confirm the development of events according to a more stringent strategic scenario. At the same time, the results for the moderate scenario are fully correlated with both the current state of the energy sector and the prospects for its development. CONCLUSION. Analysis of the current state and assessment of scenarios for the development of the energy sector of the republic's economy showed an increase in the reliability of power supply systems when organizing a "ring" in the Western Energy District; increase in useful electricity consumption by 2030; increase in electricity production; changes in the structure of electricity production.

Alumina production is rather complex technological process of processing mineral raw materials that requires development of effective technological solutions, including in terms of efficiency of using electric energy. The paper is devoted to studying the power supply system of an alumina refinery inLam Dong Province,Vietnam. The tasks that need to be solved for improving the power quality in the power supply system were analyzed. It was shown that non-linear loads significantly degrade the power quality that in turn leads to equipment damage, malfunction and decreasing the refinery productivity. Models of the refinery power supply system were developed and, using which, the quality of power was assessed at the 6 kV voltage utility bus of the power supply system, as well as at the 6 kV and 0.4 kV buses of distribution substations of individual refinery’s subdivisions. Analysis of the simulation findings showed that the nonlinear loads lead to significant distortions of sinusoidal forms of voltages and currents, and decreasing the power factor. Based on the simulation results, it was concluded that voltage harmonics and current harmonics at nonlinear load at the low voltage buses of 0.4 kV and at the buses of 6 kV exceed the permissible limits of the harmonics in accordance with IEEEST519-1992 international standard. Proposals were developed for improving the power quality in the refinery power supply system. For suppressing higher harmonics of current and voltage, it was recommended to use special power quality regulators in the alumina refinery power supply system. It was proposed to use active harmonic filters as the power quality regulators. The proposed solutions allowed obtaining practically sinusoidal forms of voltages and currents in the alumina refinery power supply system.

The paper presents the results of constructing effective relay protection in the power supply system of a mining and processing plant (MPP). A brief description of the MPP is given, the power supply and substitution circuits used to calculate the short-circuit currents are given. A statistical analysis of failures in the electric network of the MPP has been carried out, which makes it possible to draw conclusions about the nature of failures ranges. Analysis of the registered faults shows that a significant part of them are line-to-earth faults, which in most cases turn into multiphase short circuits, which are interrupted by overcurrent protection. In order to improve the efficiency and reliability of the relay protection, the power supply scheme of the MPP was refined and analyzed. The calculation of the short-circuit currents was made, which made it possible to calculate the settings of the relay protection and give recommendations on the place of its installation and adjustment in order to ensure the normal operation of electricity consumers. To reduce the number of failures to the cable insert on the line leaving the administrative and household complex (AHC), and to increase the reliability of power supply to consumers, it is advisable to divide the capacities of the existing 10 kV line into two parallel ones by laying a second line. It is recommended to install a current cut-off on the line outgoing to the AHC, the feasibility of the installation of which was shown by calculations. This will reduce the chance of failures to the cable gland. Data on the setting currents of overcurrent protection and current cut-off are given on the selectivity card.

Problem. Cleaning transformer oil is one of the important engineering tasks, whose solution is associated with significant material and energy expenditure. Due to the increase in electricity consumption at modern automobile companies (firms, organizations, service stations, etc.), the load on transformer substations increases and the requirements for reliability of electrical and electronic devices become more complicated. This, in turn, leads to the problem of cleaning and recycling of transformer oil. Goal. The goal is the research and development of an efficient unit for centrifugal cleaning of transformer oil with a drive control system that provides automation of the start and braking mode of the drive. Methodology. Analytical methods of research, methods of the theory of electric machines and electric drives are used, as well as the methods of calculating electric circuits. Also, methods of analysis of circuits and control of power electronics devices, principles of operation and methods of control of static converters are used. Results. The structural scheme of the unit for cleaning transformer oil is developed. The calculations of the main elements of the power block of the transformer oil cleaning unit are performed. The block diagram of the voltage converter with frequency f = 50 Hz to alternating voltage with frequency f = 400 Hz is developed. Control circuits of the electric drive of the centrifugal separator are chosen. The analysis of operation of electric drive control circuits is carried out and the principles of their work concerning two components are considered: the regulated rectifier and the inverter. Originality. The scheme of the converter of alternating three-phase current with voltage of 220 V and frequency of 50 Hz, into alternating three-phase current with voltage of 220 V and frequency of 400 Hz is developed. This frequency, in addition to providing the necessary characteristics of the oil separator, allows you to develop a converter device of a relatively small weight and volume, and also provides its high reliability. Practical value. Utilizing the used transformer oil in this way will solve several problems at once. It is possible to reduce the initial production of transformer oil. The issue of waste oil disposal is being resolved leading to the solution of the environmental aspect of this problem. All this will reduce the cost of oil poured into transformers and the operating cost of transformer substations.

THE PURPOSE. In remote areas in the absence of centralized power supply, energy conservation is one of the key factors for the successful development of the region. The use of electrochemical energy storage systems contributes to the saving of liquid or gaseous fuel of power plants used in autonomous power supply systems. Domestic manufacturers have created modular-type mobile energy storage systems designed for their rapid deployment in almost any territory and operating in the range from several hundred kilowatts in a single design to complexes of tens of megawatts. METHOD. The method of indefinite Lagrange multipliers was used in application to the power profiles of the load of a discrete form to select the parameters of the electrochemical energy storage, causing the minimization of fuel consumption. The obtained mathematical model uses the power profiles of the load, formed by its duration, and is focused on the simplest algorithm for the numerical search for the extremum of a function by changing its argument, without solving the optimization nonlinear equation. The method includes the choice of the duration of the discharge of the energy storage. RESULTS. The influence of the energy storage device on the reduction of fuel consumption is shown. The technique is valid for convex consumption characteristics of power plants. In the context of predicted changes in power profiles (work / weekend days), optimal control scenarios are calculated individually. CONCLUSION. The use of the proposed mathematical model provides quick calculations of the economic assessment of the use of electrochemical energy storage. For gas piston power plants, where they are required to stabilize the parameters of power quality, their commercial attractiveness is significantly higher than for power plants of another type.

Copyright of Journal of Measurement Science & Instrumentation is the property of Journal of Measurement Science & Instrumentation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The 12 V powernet in vehicles must fulfill certain safety requirements due to the safety demand of consumers. A potential risk is undervoltage for a safety-relevant consumer, which leads to its fault. Therefore, a novel approach is presented in this study, which can predict the minimum terminal voltage for consumers. This consists of diagnostics of the wiring harness and of the lead-acid battery as well as predefined consumer currents. Using simulation, first the beginning of a drive cycle is simulated to determine the state of the powernet, and afterwards a critical driving maneuver is simulated to validate the predicted minimum terminal voltage. It demonstrates that the novel approach is able to predict a fault due to undervoltage. In addition to fulfilling safety requirements, the novel approach could be used to achieve additional availability and miniaturization of powernet components compared to the state of the art. [ABSTRACT FROM AUTHOR]

As gas pipeline systems become larger and more complex, the importance of optimally operating and planning these facilities has increased. The capital costs and operating expenses of pipeline systems are so large that even small improvements in the use of the system can involve large sums of money. Purpose. This article proposes a method to improve the reliability and optimization of power supply systems for compressor stations. The novelty of the proposed work is the development of a new mathematical model that allows the choice of the most appropriate maintenance policies in the best way to significantly reduce costs as well as to optimize useful key performance indicators – failure rate, average time between breakdowns, the average repair time for equipment in compressor station electrical supply systems. Applying graph theory to represent this mathematical model from the schematic diagram of the different energy sources with respect to the five compressor stations is adequate. Methods. The problem that arises for the future operator or operator is, among others, how to balance two main aspects: a technical aspect and an economic aspect. The proposed methodology introduces a research algorithm to calculate the optimal values of the operating parameters of the power supply systems of compressor stations by combining technical and economic aspects in order to reduce costs and increase performance indicators. The proposed algorithm can be implemented in FORTRAN code. Results. The algorithm developed is an efficient tool for calculating maintenance costs and allows by means of programming to define the most appropriate maintenance policy. On the other hand, this technique could be used as an essential economic evaluation indicator for other equipment in order to choose among all the technically possible solutions the one which allow obtaining the best economic result. Practical value. The proposed algorithm has been examined in this third variant of the supply system with two turbogenerators. The result of the optimization shows a clear preference for selecting station C for the pipeline as this presents the minimum cost which is the definition of the algorithm optimizer. Then, it is important to adopt the most recommended maintenance policies and practices in order to ensure the availability of the power supply systems and to avoid unplanned outages with the resulting loss of production.

This paper analyses the validity of using superconductors in the power supply system of arc devices. Two cases were analysed: when an additional superconducting element was included in the conventional power supply system and when the total power supply system was made of a superconductor. The analysis was carried out by simulating the cooperation of the arc receiver with its simplified power supply system in Matlab Simulink software. The characteristics of the changes of the arc current, its conductance and voltage as a function of the arc length changes for selected superconductor parameters, i.e., different values of the critical current and different values of the resistance in the resistive state, are given. The time courses of these quantities as well as the courses of resistance changes in the superconductor at randomly varying arc lengths are presented. The analysis showed that by selecting the critical current and resistance in the resistive state of the superconductor, arc parameters such as arc current drawn and arc conductance can be influenced. By making the entire power system from a superconductor, the arc current can be increased by 1.8% for a 1 cm arc and by 1% for a 1 cm arc. The ability of the superconductor to lose its superconducting state and return to that state can be used to limit the value of the current drawn by the arc over certain ranges of arc length. The range of these lengths can be controlled by selecting the value of the critical current of the superconductor. By selecting the resistance of the superconductor in the resistive state, the value of the limited current can be influenced. In the case studied, for a 1 cm arc length, an arc current 45% lower was obtained when the superconductor was in the resistive state. [ABSTRACT FROM AUTHOR]

The research fields in the fields of information science and computer are very extensive, and there are many research hotspots. Intelligent optimization algorithm is one of the research hotspots. One of the key issues found in research papers in this field is how to effectively improve the search quality of intelligent optimization algorithms in a complex work environment. As a multi-functional swarm algorithm, particle swarm optimization has relatively few parameters, good convergence, and relatively fast working speed. It is a popular intelligent algorithm. In the process of studying the optimal operation of the combined cooling, heating and power system, in order to better dispatch the output of each device in the combined cooling, heating and power system, a combination of chaotic search based on Tent mapping and nonlinear adaptive particle swarm optimization is proposed Optimization algorithm. Taking the operating cost, pollutant emission and energy efficiency of the cogeneration system as the goals, a multi-objective optimization model was established. The simulation results show that the proposed cooling, heating and power cogeneration system optimization method can effectively improve economic benefits, reduce pollution emissions, and improve energy utilization. The traditional model cannot accurately analyze the environmental pollution mitigation effect. In order to avoid this problem, a modeling analysis of the impact of wind power photovoltaic clean energy on the mitigation of environmental pollution is proposed, thereby building a wind power photovoltaic clean energy organization structure and maintaining the application of wind power photovoltaic clean energy the stability of the range. Set wind power photovoltaic clean energy to alleviate environmental pollution factors, and determine the degree of environmental pollution limited by natural numbers under continuous use of polynomial constraints. [ABSTRACT FROM AUTHOR]