Journal of Electrical and power engineering最新文献

{"title":"Restoration of energy saving fuel elements after using them in a hydrogen environment.","authors":"L. E., Shtepa A.A.","doi":"10.31474/2074-2630-2022-1-69-73","DOIUrl":"https://doi.org/10.31474/2074-2630-2022-1-69-73","url":null,"abstract":"As a result of the conducted literature research the experimentally fixed positions about features of the hydrogen-induced deformation of a palladium plate are described. It is determined that when hydrogen saturation in the metal, a temporary gradient material \"metal-hydrogen\" is formed and hydrogen stress concentrations always occur. This in turn provides effective planning and determination of the time of penetration of hydrogen into the metal. The obtained experimental facts allow to control the change of shape and regulate the modes of operation of the fuel cell during the operation of the products. It is described that the maximum bending of the plate occurs at a constant temperature, and is determined by two fundamental properties of the palladium system - hydrogen, namely, the diffusion coefficient and equilibrium solubility of hydrogen in palladium. However, when the temperature changes, the diffusion coefficient of hydrogen in palladium and the equilibrium concentration of hydrogen in palladium changes, which determines the temperature dependence of the final bending of the plate and its change) when interacting with hydrogen. The scientific novelty is the use of the known material palladium, which in contact with hydrogen becomes a temporary gradient alloy with variable physical properties. It is established that the heat exchange in the plate and the energy balance around the plate depends on the rate of interaction of hydrogen and material, as well as the rate of heat flux that occurs during chemical reactions in fuel cells and heat loss in the fuel cell. The practical significance of the work lies in the possibility of using certain physical bases in practice in the manufacture of specific devices that work as a fuel cell with hydrogen. You can also model this process in MaCad and improve the operating conditions of fuel cells and hydrogen sensors, because at low temperatures there is a relatively small residual bending of the main components, and accordingly there are changes in the shape of these components.","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123776147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Higher harmonics of zero sequence current and voltage as a source of information for single-phase earth fault protection.","authors":"В Ф Сивокобиленко, Донецький національний технічний університет, Лисенко В.А","doi":"10.31474/2074-2630-2021-1-25-32","DOIUrl":"https://doi.org/10.31474/2074-2630-2021-1-25-32","url":null,"abstract":"Single-phase earth faults in networks with ungrounded neutral are common and belong to a wider class of high-impedance damage. The problem of protection against such damage is quite complex and has been actively studied around the world in recent decades. In this article, it is proposed to use the information contained in the high-frequency components of the current and voltage of the zero-sequence during the transient process of insulation damage for targeted protection. The method of selection of high-frequency components is considered. The possibility of using a Petersen coil in the network is considered, as well as the probable deviation from the resonant tuning of the Petersen coil. The peculiarities of the transient process depending on the instantaneous voltage at the moment of a short circuit are investigated. Simulation of single-phase short circuits with different active resistance in the short circuit place is carried out. The spectral composition of zero-sequence currents and voltages during the transient process is analyzed. The dependence of the power of high-frequency components on the quality of Petersen coil tuning, instantaneous voltage at the time of short circuit, and active resistance at the time of short circuit is investigated. The principle of protection is based on determining the direction of the total reactive power of the higher harmonics of currents and voltages of zero sequence and the numerically found derivatives. The results of mathematical modeling showed that at the moment when the phase is closed to the ground, due to the recharging of the capacitance of the phase conductors in currents and voltages of zero sequence, higher harmonics occur. The power of the harmonics from the second to the tenth can be compared with the power of the first harmonic and they should be used for protection. Positive results of work of the offered way of protection at mathematical modeling and at tests on a laboratory stand are received.","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133415244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grid-tied photovoltaic system with a storage battery to supply the local object own needs with multi-zone payment","authors":"О. Shavelkin, І. Shvedchykova","doi":"10.31474/2074-2630-2020-2-6-15","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-6-15","url":null,"abstract":"The principles for the implementation of control and redistribution of energy in a photovoltaic system with a storage battery for a local object connected to a grid with multi-zone tariffication have been improved, with the exclusion of generating electricity to the grid. There is a synthesis of the structure of the control system and the control algorithm based on the analysis of processes in electrical circuits using computer modeling to substantiate the system parameters and check the proposed solutions. The possibility of ensuring the normal functioning of a local object for a possible violation of the quality of electricity during the most loaded peak hours and most of the daytime during the autonomous operation of the system is shown. Relationships are obtained for determining the values of the input voltage of the inverter, the inductance of the reactor and the PWM frequency when the inverter is operating in the active rectifier mode with the possibility of reducing the PWM frequency in the autonomous mode with a decrease in energy losses in the switches and an increase in efficiency. The structure of the control system has been improved to ensure that the battery operates in the active zone of charging characteristics in an autonomous mode and switching the load to the grid when the inverter charges the battery in the active rectifier mode. The simulation model of energy processes in the system has been improved, taking into account the charging and discharging characteristics of the battery. It has been established that the lowest costs for electricity consumed from the network are achieved at maximum loads during peak hours, the ratio of the capacities of photoelectric and storage batteries is justified. The performance of the proposed solutions is confirmed by modeling in Matlab and on an experimental setup based on a standard hybrid inverter. The solutions obtained are the basis for the design of new and modernization of existing photoelectric systems of local objects, including the use of software and hardware control systems.","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131159752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A software-hardware complex for controlling a photoelectric system with a battery to provide for the own needs of a local object connected to the grid.","authors":"O. Shavolkin, I. Shvedchykova, H. Kruhliak, Y. Stanovskyi, M. O. Pidhaynyy","doi":"10.31474/2074-2630-2020-2-20-27","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-20-27","url":null,"abstract":"The software and hardware complex for managing the generation and redistribution of energy in a photovoltaic system with a battery, which provides the own needs of the local object connected to the grid with a three-zone tariffication is presented. A decrease in the cost of paying for electricity consumed from the grid is achieved by using cheaper energy during peak hours with matching the load with the generation of a photovoltaic battery and the degree of charge of the battery. There is a proposal to forming","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124372878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving the operation of the linear electromagnetic step device.","authors":"V. Smolianinov, A. Sukhopara, Ukraine Production Enterprise Mti Kyiv","doi":"10.31474/2074-2630-2020-2-38-43","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-38-43","url":null,"abstract":"The improved operation of the linear electromagnetic device (LED) is proposed, without the use of additional sensors for control motion of mobile link LED and automation of technological process. Research focused on determination of the relationship of changes in active inductive parameters of the LED with its design parameters when moving the mobile link of LED and construction an improving the operation, that controls these changes for the increasing the efficiency of their functioning. For this research a theories of electrical circuits and electronic circuits were implemented, which takes into account the change in electrical parameters when moving the mobile link of the linear electromagnetic device. It is proved the dependence of the magnetic resistance in certain sections of the magnetic circuit from the position the mobile link and the design parameters of the LED, the intervals of the magnetic resistance change when the mobile link is moved by the size of the step. The accordance is found between the change in active - inductive parameters when the position of the moving link","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122486288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of operating modes of squirrel-cage induction motors in the presence of damage to the rotor rods.","authors":"E. Niemtsev","doi":"10.31474/2074-2630-2020-2-59-64","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-59-64","url":null,"abstract":"The article determines that the main faults in induction motors are damage to the stator and rotor windings, which occur due to changes and distortions in the shape and amplitude of the supply voltage, technological overheating of the windings, mechanical damage. These factors lead to accelerated wear of the insulation of the windings, structural components of the motors, increased values of power losses and the occurrence of pre-emergency and emergency situations. Among the specified diagnostic parameters of engine operation it is possible to consider separately existence of damages of cores of a short-circuited rotor which timely diagnostics demands removal of the engine in repair and will allow to avoid emergency situations with induction motors. To diagnose the control of the rotor rods are quite diverse: determining the amplitude-frequency spectrum of stator currents, detecting the presence of current ripples in an artificial short circuit in the stator winding, the use of diagnostic curves, the selection of appropriate harmonic oscillations in the vibration of the rotor. To reduce or eliminate the negative impact of various factors on the course of technological processes, the best approach at present is the use of tools and measures to diagnose the operation of engines using modeling methods. Based on the model of an induction motor with a short-circuited rotor created in the MATHCAD software environment, graphical dependences were obtained that reflect the change of the main parameters of the induction motor operation and allow to analyze their change during the modulation time. The presence of pulsations of regime parameters and aperiodic components caused by transients was shown. Studies of the process of starting the engine without load and under load showed an increase in start-up time, and the pulsating nature of the studied parameters is observed only in the initial section. The engine start time also increases in the presence of damaged rods in the short-circuited rotor. The pulsating nature of the main diagnostic parameters can be used as a criterion for determining the presence of damage in the short-circuited winding of the rotor of an induction motor.","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115273616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the influence of overvoltage on the quality of electricity in energy systems.","authors":"S. Skrypnyk","doi":"10.31474/2074-2630-2020-2-52-58","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-52-58","url":null,"abstract":"Our world with its high technologies has long been deeply dependent on the quality of electricity supply. In most countries of the world there are national power grids that combine the entire set of generating capacity and loads. This network provides the operation of household appliances, lighting, heating, refrigeration, air conditioning and transport, as well as the functioning of the state apparatus, industry, finance, trade, health services and utilities across the country. Without this utility, namely electricity, the modern world simply could not live at its current pace. Sophisticated technological improvements are firmly rooted in our lives and workplaces, and with the advent of e-commerce began the process of continuous transformation of the way individuals interact with the rest of the world. But with the achievement of intelligent technologies, an uninterrupted power supply is required, the parameters of which exactly meet the established standards. These standards maintain our energy security and create a reliable power system, that is maintaining the system in a trouble-free state. Overvoltage is the deviation of the rated voltage from the value of the corresponding quality standard (frequency, sinusoidal voltage and compliance of harmonics). Overvoltage in terms of fire hazard is one of the most dangerous emergency modes of electrical equipment, which causes conditions that in most cases are sufficient for the occurrence of fire hazards (exceeding the allowable voltage leads to disruption of normal operation or possible ignition). Against the background of deteriorating engineering systems, increased power consumption and poor maintenance, power supply of electrical installations, the main causes of overvoltage in electrical networks are thunderstorms (atmospheric overvoltage), switching switches, uneven phase load in electrical networks, etc. The physical picture of internal overvoltage is due to oscillatory transients from the initial to the established voltage distributions in the conductive sections due to the different situation in the electrical circuit. In the conditions of operation of electric networks planned, mode or emergency situations are possible. Therefore, the ranges of overvoltage are determined by the range from several hundred volts to tens and hundreds of kilovolts, and depend on the types of overvoltage. Atmospheric overvoltage is considered to be one of the most dangerous types of emergency modes of operation of the electrical network. This overvoltage occurs as a result of lightning discharge during precipitation by concentrating electricity on the surface of the object, the introduction of potential through engineering networks and","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127842826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of voltage regulation devices.","authors":"N. Tiutiunnyk, G. Sheina","doi":"10.31474/2074-2630-2020-2-44-47","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-44-47","url":null,"abstract":"The paper considers an electrical substation with a voltage of 330/110/35 kV. Means of voltage regulation on the substation autotransformer are investigated. The paper considers the means of voltage regulation on autotransformers of the 330/110/35 kV substation to ensure uninterrupted power supply and the desired voltage level on the busbars of consumers. The choice of the optimal version of the on-load tap-changer of the autotransformer is shown. The electric network with voltage of 110 and 35 kV is considered. The power supply center is substation 330 kV. The connection between voltages is provided by three three-phase autotransformers of the ATDCTN200000/330/110 type. Autotransformers are used instead of three-winding transformers to reduce the cost of conductive material and increase transmission power, but unlike three-winding transformers, they have only one voltage control device - load control regulation. Steady-state and emergency modes are investigated. The PowerFactory program has created a network model, which is used to calculate the mode and evaluate the methods of voltage regulation. On the basis of calculations the point of economic flow distribution in which it is expedient to open a network in a normal mode, and on the switch to provide the device of automatic input of a reserve is defined. The principles of control of modes of operation of electrical systems are investigated: minimum costs for generation, transmission and consumption of electricity (technological losses), reliability of operation of electrical systems, quality of electricity. The purpose of this work is to substantiate the optimal operational scheme of the electrical network, the study of the modes of operation of the 330/110/35 kV network. The simulation of steady and emergency modes is performed in the work. The optimal operational scheme of the electric network is substantiated in order to improve the reliability of power supply and ensure the desired level of voltage on the busbars of consumers.","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132577868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the synchronous motors behavior in the transients for backup power supply. Purpose.","authors":"V. Syvokobylenko, V. Lysenko, Syvokobylenko","doi":"10.31474/2074-2630-2020-2-28-37","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-28-37","url":null,"abstract":"Simulation of transient and steady state modes of synchronous motors for the analysis of switching to backup power using mathematical model. Method. The methods of linear algebra, numerical optimization methods, methods of modeling and analysis of established and transient modes are used. Results. The mathematical model of the salient pole rotor and non-salient or cylindrical pole rotor synchronous motor is presented, which is presented in the form of a alternate scheme, which allows to take into account the effect of displacement of current and saturation of the non-salient pole rotor motor's magnetic core. A method for determining the parameters of the synchronous motor based on passport data is proposed, which allows to improve the accuracy of modeling in steady state and transient modes. The mathematical model is reduced to a three-phase coordinate system a, b, c of the stator winding. The rotor windings are modeled in the coordinates d, q. The results of mathematical modeling allow us to determine the magnitude of the shock currents and mechanical moments of the synchronous motor. It is shown that non-synchronous switching on of the synchronous motor, which occurs in case of automatic transfer switch, can lead to engine damage. Shock currents can also be dangerous to other power supply equipment. Thus, synchronous motors, if transfer switch is used, require synchronization before being connected to the network. Scientific novelty. The mathematical model of the synchronous motor was improved taking into account the displacement of current and saturation of the magnetic conduit, the method of determining the parameters of the mathematical model based on the passport data of the engine was improved, which allowed to increase the accuracy of the simulation and the reliability of the simulation results. The modes of power transfer switch are simulated and the values of shock current and shock mechanical moment of the engine are obtained. Practical meaning. The mathematical model of the synchronous motor allows to analyze the behavior of synchronous motors in interaction in the power supply system and to identify the dangerous states of synchronous motors that may occur during the transfer switching. The proposed model improves the accuracy of determination of the limits of dangerous states and improves the reliability of synchronous motors and power supply systems.","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117169460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of alternative energy of Ukraine in the context of energy and environmental security of the state.","authors":"I. Prydatko, O. Kollarov, N. Tyutyunnyk, D. Kardash","doi":"10.31474/2074-2630-2020-2-87-91","DOIUrl":"https://doi.org/10.31474/2074-2630-2020-2-87-91","url":null,"abstract":"Increased greenhouse gas emissions, climate change; loss of diversity of fauna and flora, depletion of mineral deposits, accumulation of huge volumes of industrial waste, increasing risks of shortages of some types of energy has led to the development and reaching new levels of renewable energy in many countries, mainly with strong economies. To date, a number of EU countries have virtually abandoned traditional nuclear energy, virtually curtailed fuel energy using nonrenewable fossil resources, and are working hard to develop new energy-saving technologies. In Ukraine, there is a similar tendency to reduce the production of electricity from thermal power plants and increase the share of renewable energy in total production. Unfortunately, in 2020 the structure of electricity production in Ukraine has changed and does not correspond to global trends in energy development. The share of electricity generation at TPPs has increased significantly, and the share of cleaner and cheaper NPP generation has decreased to 40%. There are a number of reasons for this, but we consider it urgent to return to the process of reducing TPP generation capacity. The dynamics of renewable energy development in the country is quite positive. Additional measures are also needed to ensure the safety of nuclear energy - to finally eliminate dependence on Russian fuel. Many countries have decided to abandon cars with internal combustion engines altogether. In Ukraine, the market for electric cars is also developing and the demand for such cars is growing every month. We are among the top 5 countries in terms of market development dynamics. The development of car designs with so-called \"nuclear batteries\" cannot be ruled out. There are many such technologies, but all of them are currently unfinished and limited in the use of security issues. It is necessary to stimulate the development of hydrogen and electric transport in our country at the legislative level. And last but not least: in order to form a philosophy of ecological consumption among the citizens of Ukraine, it is necessary to develop appropriate government programs, introduce them in education, science and industrial production","PeriodicalId":174144,"journal":{"name":"Journal of Electrical and power engineering","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130100967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}