Electrical Engineering & Electromechanics最新文献

{"title":"TECHNOLOGICAL MONITORING OF ELECTRICAL RESISTANCE OF PRESSED CABLE CONDUCTORS IN PRODUCTION CONDITIONS","authors":"Y. Antonets, L. Shchebeniuk, O. M. Grechko","doi":"10.20998/2074-272x.2019.4.07","DOIUrl":"https://doi.org/10.20998/2074-272x.2019.4.07","url":null,"abstract":"Представлено результати контролю в умовах виробництва електричного опору R пресованих алюмінієвих кабельних провідників. Контроль R в кабельному виробництві є наймасовішим неруйнівним випробуванням, яке забезпечує компроміс між затратами виробника на матеріал високої електропровідності з одного боку, і експлуатаційними затратами користувача від втрат на нагрівання провідників з іншого. Для прийняття технологічних рішень щодо використання гарячого пресування суцільних алюмінієвих жил (замість технології холодної витяжки) для конкретних розмірів жили необхідне надійне визначення ймовірності появи недопустимих значень електричного опору R > Ř (ймовірності рекламацій) у великих масивах продукції. Розглянуто застосування статистичного аналізу результатів вимірювання за допомогою математичного апарату граничних розподілів. При цьому предметом аналізу стає розподіл граничних значень контрольного параметру, що дає можливість надійного оцінювання ймовірності появи недопустимих значень (ймовірності рекламацій). Розроблено алгоритм визначення ймовірності появи недопустимих значень електричного опору R > Ř (ймовірності рекламацій) для суцільних алюмінієвих жил силових кабелів низької і середньої напруги в діапазоні площі поперечного перерізу (120…240) мм 2 на основі аналізу результатів контролю електричного опору впродовж тривалого технологічного періоду (18 місяців) виготовлення в умовах виробництва. Запропоновано використання рекламаційного потенціалу технологічного рішення як вартості продукції, для якої R > Ř. Виконане порівняння рекламаційного потенціалу технології гарячого пресування суцільних алюмінієвих і технології холодної витяжки (волочіння) за умови досягнення однакового рівня питомої електропровідності металу.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49200910","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":"PECULIARITIES OF THE MANIFESTATION AND INFLUENCE ON THE ELECTROMAGNETIC PROCESSES OF THE TRANSIENT SKIN EFFECT IN METAL CONDUCTORS WITH PULSED CURRENT","authors":"M. I. Baranov","doi":"10.20998/2074-272x.2019.4.06","DOIUrl":"https://doi.org/10.20998/2074-272x.2019.4.06","url":null,"abstract":"Приведен краткий обзор результатов известных теоретических исследований электрофизического явления линейного нестационарного поверхностного эффекта (НПЭ) в немагнитных однородных массивных плоских и цилиндрических металлических проводниках с импульсным аксиальным (азимутальным) током, формируемым в разрядной цепи высоковольтной электрофизической установки (ЭФУ) . В обобщенном и систематизированном виде представлены основные особенности проявления линейного НПЭ в указанных проводниках и влияния рассматриваемого скин-эффекта на электромагнитные процессы, протекающие в проводниках и разрядной цепи ЭФУ с импульсным током, изменяющимся во времени по закону затухающей синусоиды. Описано влияние линейного НПЭ на длительность переходного процесса в разрядной цепи ЭФУ, глубину проникновения электромагнитного поля в материал проводников, собственные электрические параметры проводников и их добротность в разрядной цепи ЭФУ.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49641560","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":"ENERGY COMMITMENT: A PLANNING OF ENERGY CARRIER BASED ON ENERGY CONSUMPTION","authors":"M. Dehghani, Z. Montazeri, O. Malik","doi":"10.20998/2074-272x.2019.4.10","DOIUrl":"https://doi.org/10.20998/2074-272x.2019.4.10","url":null,"abstract":"Purpose. Energy consumption is one of the criteria for determining the quality of life in a country. Continued supply of energy and the possibility of long-term access to resources require a comprehensive plan. One of the key issues in the field of energy planning is energy carriers. In this paper, a new theory is introduced to energy network studies for planning of energy carriers called Energy Commitment. In this theory, an appropriate planning is applied for energy carriers based the final energy consumption. Energy carriers are available either naturally or after the energy conversion process. Energy commitment is modeled on an energy network with the presence of electrical energy, gas energy, transportation section, agriculture section, industrial section, residential section, commercial section, and general section.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42411474","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":"INVESTIGATION OF AMPLITUDE-TEMPORAL CHARACTERISTICS OF A HIGH-VOLTAGE RESISTIVE VOLTAGE DIVIDER","authors":"N. Boyko, S. O. Syomkin","doi":"10.20998/2074-272x.2019.4.09","DOIUrl":"https://doi.org/10.20998/2074-272x.2019.4.09","url":null,"abstract":"Цель. Определение возможности использования разработанного автономного делителя напряжения для измерения высоковольтных импульсов с обостренными фронтами (до 1 нс). Методика. Применена методика определения коэффициента деления делителя при помощи калиброванного генератора и осциллографа. Для определения времени нарастания переходной характеристики делителя использовалась экспериментальная методика на основе генератора высоковольтных импульсов с крутым фронтом и компьютерное моделирование с использованием программы схемотехнического моделирования Micro-Сap. Результаты. Экспериментально получены осциллограммы высоковольтных наносекундных импульсов с субнаносекундными фронтами при помощи созданного автономного резистивного делителя напряжения. Проведено компьютерное моделирование работы созданного делителя в различных режимах. Научная новизна. Показано, что автономный экранированный резистивный делитель высокого напряжения может иметь время нарастания менее 1 нс. Установлены величины паразитных параметров делителя, приводящих к искажению обостренного фронта импульсов с временем нарастания ≈0,1 нс. Практическая значимость. Делитель можно применять для измерения характеристик высоковольтных импульсов с крутым фронтом (до 1 нс как нижней границы).","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49106399","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":"SYNTHESIS AND ANALYSIS OF ARC FURNACE ELECTRICAL MODE CONTROL SYSTEM ON THE BASIS OF THREE-DIMENSIONAL PHASE CURRENTS VECTOR DISTRIBUTION","authors":"O. Lozynskyi, A. Lozynskyi, Y. Paranchuk, R. Paranchuk","doi":"10.20998/2074-272x.2019.4.04","DOIUrl":"https://doi.org/10.20998/2074-272x.2019.4.04","url":null,"abstract":"Мета. Метою статті є створення методу оперативного синтезу сигналу керування електричним режимом (ЕР) дугової сталеплавильної печі (ДСП) на основі тривимірного вектора струмів фаз, що враховує стохастичну природу процесів у плавильному просторі, силовому електричному колі печі, має низьку чутливість до зміни параметрів об’єкта керування та розроблення структури системи керування для його реалізації. Методика. В основу створеного методу керування покладено положення статистичної теорії динамічних систем, а також положення статистичної теорії оптимального керування на основі рівняння Фоккера-Планка-Колмогорова, що дає змогу синтезувати оперативне керування за критерієм наближенням густини розподілу регульованої координати до d-функції, тобто мінімізувати дисперсію тривимірного вектора струмів фаз (дуг) дугової печі. Результати. Отримано систему рівнянь для оперативного в режимі on-line розрахунку керуючих впливів тиристорного комутатора фазних дроселів, що включені у силове коло живлення трифазних дуг, та структурну схему адаптивного контура формування дисперсії тривимірного вектора струмів дуг дугової печі для реалізації адаптивного оптимального керування. Наукова новизна. Вперше на основі рівняння Фоккера-Планка-Колмогорова отримано систему рівнянь, що подають математичну модель стохастичного адаптивного оптимального керування електричним режимом дугової сталеплавильної печі за критерієм мінімуму дисперсії тривимірного вектора струмів дуг, що дає змогу у порівнянні з відомими методами підвищити динамічну точність стабілізації струмів дуг на рівні заданих за критеріями енергоефективності та електромагнітної сумісності значень. Практична цінність. Реалізація запропонованої моделі адаптивного оптимального керування та структурної схеми системи для її реалізації дасть змогу у порівнянні з серійними регуляторами потужності дуг поліпшити динамічну точність стабілізації струмів дуг на рівні заданих оптимальних уставок і на основі цього комплексно поліпшити показники енергоефективності та електромагнітної сумісності режимів дугової печі та електромережі.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48261923","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":"PARAMETRIC ANALYSIS AND STRAY FIELDS OF TOROIDAL SUPERCONDUCTING MAGNETIC ENERGY STORAGE","authors":"Y. Vasetsky, I. Mazurenko, S. Bondarevskyi","doi":"10.20998/2074-272X.2019.3.05","DOIUrl":"https://doi.org/10.20998/2074-272X.2019.3.05","url":null,"abstract":"Purpose. To carry out a parametric analysis of superconducting toroidal magnetic systems with a discrete winding, establishing the possibility of using an idealized model in the form of a toroidal current surface and an approximate method for determining the level of fields of scattering of a real magnetic system. Methodology. The calculation of the distribution of the magnetic flux density in the winding, the field of scattering and energy of the storage’s field was carried out using asymptotic methods for solution of the problems of electrodynamics in systems with massive curvilinear conductors with current. An iterative calculation procedure was used to determine the dimensionless characteristics. Results. The dimensionless characteristics of a toroidal magnetic system with a winding in the form of individual superconducting coils of circular shape are calculated. The results are obtained depending on the value of the storage's energy capacity for various values of the relative radial size of the torus. For a toroidal superconducting storage device with energy capacity of 450 MJ, enough to perform the function of damping irregular oscillations of power transmitted over the transmission line, magnetic fields of scattering are calculated for different numbers of coils and torus section sizes. Originality. Based on a comparison of the values of dimensionless characteristics calculated for a system with individual coils, and for an idealized mathematical model of a continuous current surface, it was established that the relative deviation of the dimensionless characteristics does not exceed 10 %. In contrast to the idealized model, the magnetic field of a toroidal system composed of individual coils spreads beyond the toroidal surface and decreases the faster, the smaller the relative radial sectional size of the torus, the greater the number of coils used and the closer they are to each other. Practical value. The results obtained for dimensionless characteristics allow to conclude that the idealized model can be used at the first stage of the development of a superconducting inductive storage. The estimation of the field of scattering can be made on the basis of a simple model of unidirectional current filaments.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46104563","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":"TECHNOLOGICAL PARAMETERS OF THE COOLING MODE OF POLYMER INSULATION OF POWER CABLES","authors":"G. Bezprozvannych, I. Mirchuk, A. G. Kyessayev","doi":"10.20998/2074-272X.2019.3.07","DOIUrl":"https://doi.org/10.20998/2074-272X.2019.3.07","url":null,"abstract":"Introduction. The cooling mode of polymer insulation after application to the extruder is one of the main factors determining cable performance. Theoretically, it is ideal to cool the insulation when the temperature of the cooling medium is equal to the melting point of the insulation material: in this case, the probability of formation of voids in the insulation is less. The cooling process is usually not subject to stringent requirements, since most insulating materials allow for quite sharp cooling. The exception is polyethylene, which requires gradual cooling. When the insulation is cooled in a cooling bath, the temperature decrease starts from the surface. In this regard, the cooling of the insulation of polyethylene is carried out in steps to a temperature at which the cooled extruded insulation will not be deformed or damaged on the receiving drum. Polyethylene is characterized by a large value of thermal expansion coefficient, the maximum value of which is in the temperature range (90-125) C. As a result, there is an uneven reduction in the volume of the upper and inner insulation layers, especially for cables with a considerable insulation thickness. The rapid cooling of polyethylene leads to the formation of cracks, air inclusions both between the insulation and the conductive core, and in the layers located near the core. Purpose. The substantiation of the technological parameters of the cooling mode of power cables based on the calculation of the thermal equivalent circuit of a conductive core insulated with polyethylene in transient thermal mode. Methodology. The calculation of the temperature distribution in the thickness of extruded polyethylene insulation at different points in time, depending on the temperature of the cooling water, is made by the method of electrothermal analogies. There is a transition from the thermal equivalent circuit of power cables to the equivalent circuit of the discrete resistive equivalent circuit method, which is calculated using the nodal potential method. As a result of solving a three-diagonal system of linear algebraic equations by sweeping and finding at each discretization step (time step) thermal power fluxes in the branches of the thermal equivalent circuit, the temperature in the thermal capacitances determines the temperature in each insulation layer. Practical value. The duration of the transition process, corresponding to the achievement of the same temperature throughout the thickness of the insulation, can be considered as a criterion in determining the length of the cooling bath sections depending on the extrusion (reception) rate. References 12, figures 6.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42270066","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":"MODERNIZATION OF THE COMPLEX TYPE IK-1U FOR MEASURING THE IMPEDANCE OF THE GROUNDING DEVICE OF A LIGHTNING ARRESTER AND SUPPORTS OF TRANSMISSION LINES","authors":"D. Koliushko, S. Rudenko, A. V. Plichko, V. Shcherbinin","doi":"10.20998/2074-272x.2019.3.09","DOIUrl":"https://doi.org/10.20998/2074-272x.2019.3.09","url":null,"abstract":"Purpose. The creation of a measuring device for determining the impedance of the grounding of lightning arresters and supports of overhead lines under the influence of aperiodic pulses with the parameters 1.2/50 μs, 8/20 μs and 10/350 μs. Methodology . For this purpose, electrical engineering theory, transient modeling software and natural modeling methods are used. Results . The parameters of the electrical circuits of the additional forming unit were determined to create lightning current pulses with parameters of 10/350 μs using the IK-1U measuring complex. According to the simulation results, a layout of the forming unit in the form of an attachment and the IK-1U complex with the upgraded power supply system were created. Oscillograms of the front and pulse duration are obtained. The specified model was tested when performing electromagnetic diagnostics of the state of the RFP for more than 100 operating electrical substations. Originality . The measuring complex IK-1U was improved, which made it possible to determine the impulse impedance of the grounding device of lightning arresters when exposed to a current of 10/350 μs, 8/20 μs and of voltages 1.2/50 μs. Practical value. Upgraded device allows measurements in accordance with modern international requirements.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44089478","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":"CALCULATION ESTIMATION OF OVERVOLTAGE ON INSULATION OF THE EQUIPMENT OF A SUBSTATION AT THE LIGHTNING STRIKE IN ITS LIGHTNING ARRESTER","authors":"I. V. Nizhevskyi, V. I. Nizhevskyi","doi":"10.20998/2074-272X.2019.3.11","DOIUrl":"https://doi.org/10.20998/2074-272X.2019.3.11","url":null,"abstract":"Purpose. The complex approach to calculating thunderstorm overvoltage on substation equipment is considered when lightning strikes in a lightning rod. Methodology. The conditions of safe passage of lightning current through a lightning arrester are formulated. Results. It is shown that the calculation of the permissible length of air insulating gaps in the substation is based on the breakdown of the air tension, which is assumed to be 500 kV/m. This leads to an error in calculating the length of the air gap and, as a consequence, the probability of its breakdown, the value of which is used to calculate the indicator of the lightning resistance of the substation. A technique is proposed for calculating the permissible voltage on the transformer case when a lightning strike strikes the lightning receptacle of the transformer portal. On the basis of the nonlinear pulsed electric strength of the ground, the specified minimum permissible ground distance between the grounding rod of the lightning rod and the nearest point of the protected device is obtained. Originality. Refined calculation of the length of the minimum breakdown gap in the air and in the ground. Practical value. The proposed approach makes it possible to calculate thunderstorm overvoltage on substation equipment. References 11, tables 4, figures 6.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45096821","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":"APPLICATION OF THE COMPUTING ENVIRONMENT MAPLE TO THE CALCULATION OF THE DYNAMICS OF THE ELECTROMAGNETS IN THE COMPLICATED SYSTEMS OF FORCED CONTROL","authors":"E. Baida, M. Clemens, B. Klymenko, O. Korol, P. Pustovoitov","doi":"10.20998/2074-272X.2019.3.03","DOIUrl":"https://doi.org/10.20998/2074-272X.2019.3.03","url":null,"abstract":"General description of the research topic. The authors propose a technique for calculating the dynamics of electromagnets operating in complex forced systems. Such forced electromagnets are widely used in electromechanical switching devices, in particular in vacuum contactors, to reduce their size, energy consumption and to increase speed, which indicates the relevance of this topic . A mathematical model of the dynamics of a forced electromagnetic system, which takes into account the peculiarities of behavior in transients of its individual elements – the mechanical system, the magnetic and electrical circuits, taking into account the interaction of the electromagnet with a control device when the apparatus is activated, contains certain signs of scientific novelty and is the purpose of the paper . The technique of calculating the dynamics of forced electromagnets uses the computing environment Maple. The calculation is based on a mathematical model, which is a system of nonlinear differential equations of the magnetic and electric circuits, supplemented by the equations of motion of the elements of a mechanical system. The use of the computing environment Maple, applied here to automatically perform the mathematical transformations, allows avoiding the complicated processes of choosing the numerical integration method, programming of complex and cumbersome equations and numerical integration procedures, to obtain results of calculations in convenient tabular and/or graphic form. This specifically indicates the practical significance of this work. The results of the comparison of calculations with previously published experimental data presented in the paper indicate the high efficiency of the proposed models and techniques.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2019-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47807810","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}