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2-х режимний тягово-левітаційний модуль перспективної магнітно-левітаційної транспортної системи
(Кременчуцький національний університет імені Михайла Остроградського, 2022) Плаксін, Сергій Вікторович; Муха, Андрій Миколайович; Устименко, Дмитро Володимирович; Шкіль, Юрій В.; Голота, Олександр Олександрович; Чуприна, Єгор М.
UKR: Сучасний електрорухомий склад має можливість розвивати швидкості руху понад 500 км/год, що створює умови для конкурентної боротьби з іншими видами транспорту на малих та середніх відстанях. Такі високошвидкісні системи на базі ефекту магнітної левітації можуть використовувати електромагнітну або електродинамічну підвіску. Перша вимагає високої точності побудови шляхової структури та складної системи управління, а друга менш критична до точності побудови шляхової структури та рівня складності системи управління, але ефектний підвіс магнітоплану створюється лише на відносно високій швидкості руху. На початкових, розгінних ділянках поїзди з електродинамічним підвісом підтримуються в робочому положенні за допомогою спеціальних колісних систем, що є суттєвим недоліком. Метою досліджень є визначення можливих схемних рішень шляхового модуля, який може забезпечувати комбінований режим роботи – режим тяги та режим левітації, не тільки у сталому режимі руху, але й на ділянках розгону чи гальмування без використання опорних колісних систем. В статті представлені деякі результати розробки тягового-левітаційного модуля на базі дворежимної шляхової структури, яка може працювати зі зміною полярності (напрямку) магнітного потоку, який взаємодіє з магнітним потоком надпровідних магнітів встановлених на магнітоплані. За результатами досліджень представлені схемні та конструктивні рішення науково-обґрунтованого тягово-левітаційного модуля для магнітнолевітаційної транспортної системи типу Маглев, з можливістю отримувати левітацію магнітоплану на розгінний ділянці.
Analysis of Operational Characteristics of SRM in Emergency Modes of the Converter Unit
(IEEE, 2022) Vlasenko, Vladimir; Tytiuk, Valerii; Kuznetsov, Vitalii V.; Kuntush, Yelena; Chornyi, Oleksii; Busher, Victor
ENG: The paper analyzes the issues of maintaining the operability of a switched reluctance motor (SRM) in various emergency situations. The researches were carried out using simulation modeling in the Matlab environment, the developed model was used for both normal and emergency operation modes. A series of dynamic tests of the motor torque has been carried out, and the values of the electromagnetic torque pulsation coefficient have been calculated. The possibility of maintaining the operability of SRM in the event of various emergency situations in the phases of the motor has been proved. The static mechanical characteristics of the motor are built and the calculation of the droop of the mechanical characteristics for possible emergency modes is performed. © 2022 IEEE.
Correlation Theory of Casual Processes in Electrical Power Problems for Systems of Electric Transport (preprint)
(IEEE, Lviv, 2015) Kostin, Nickolai A.; Mishchenko, Tatyana M.; Shumikhina, Lyudmila
ENG: A new method is proposed for determining the energy indices in electric transport systems, based on the correlation theory of random processes. According to this method, the components of apparent power and power factor are expressed through correlation functions and mathematical expectations of investigated traction voltages and currents. Numerical calculations of active, reactive and apparent power as well as the ratio of reactive power for a traction substation feeder show that the method possesses high accuracy: the error is less than 2%.
Determination of Energy and Electric Capacity of On-Board Supercapacitor Regenerative Energy Storage
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2021) Kostin, Mykola O.; Mukha, Andrii M.; Sheikina, Olha H.; Kurylenko, Olena Ya.
ENG: Purpose. Development of a method for determining the main functional parameters of on-board supercapacitor recuperative energy storage based on the asymptotic theory of extreme statistics by Gumbel, taking into account sto-chastic nature of changes in recuperated voltage and current. Methodology. To achieve this purpose, methods, devices and computer systems for temporary registration of recuperated voltages and currents on operating electric locomotives, methods of the theory of random processes and methods of probabilistic and statistical processing of registro-grams of voltages and currents were used. Findings. A computational and experimental method for estimating recu-perative energy has been proposed and practically applied. A probabilistic method has been developed for determining the energy and electric capacity of on-board supercapacitor recuperative energy storage units. Numerical probabilistic and statistical calculations of the energy and electric capacity of on-board storage for the VL8 and VL11M6 electric locomotives during their operation in the sections of Prydniprovska railway have been carried out. It was found that the energy and electric capacity of on-board storage devices are distributed according to an exponential law with a clear prevalence of their minimum values and in compliance with direct proportionality between them. Originality. For the first time, an autonomous phase of recuperative braking mode of an electric rolling stock has been developed, which makes it possible to significantly reduce the mass and dimension of a supercapacitor storage. The asymptotic theory of extreme statistics by Gumbel was adapted to the method for calculating energy and electric capacity of an on-board storage device, which made it possible to take into account the influence of stochastic nature of changes in the recuperated voltage and current. The probabilistic influence regularities of the change nature in the recuperation energy on the capacity of on-board storage in the phase of recuperative braking have been established. Further development was obtained by a computational-experimental method for assessing the recuperative energy, based on monitoring and using the time dependences of voltage and current obtained in real modes of recuperative braking. For the first time in electric traction systems, it was proposed to carry out the transition from the recuperative braking mode to the recuperative regeneration mode. Practical value. The developed method and technique based on it make it possible to evaluate functional parameters of on-board storage device of all types of electric rolling stock, considering stochastic nature of recuperated voltages and currents. Numerical-graphic dependences of the energy in-tensity and capacity of the on-board storage are recommended for predicting and evaluating these parameters for various modes of recuperative braking. Since the task of designing an on-board storage unit (in terms of mass and dimensions) is ambiguous, therefore, in each specific case of the type of electric locomotive and recuperation modes, it must be solved individually, taking into account the probability of the corresponding capacitance values.
Development of a Diagnostic Procedure for Assessing the Performance of a Magnitoplane Navigation System
(TECHNOLOGY CENTER PC, Kharkiv, 2025) Plaksin, Serhiy; Mukha, Andrii M.; Ustymenko, Dmytro V.; Podchasov, Andrii; Holota, Oleksandr
ENG: The object of research is the process of ensuring the reliability of high-speed magnetic levitation. Navigation tasks of high-speed ground transport require high accuracy and reliability along with high speed of obtaining data on the location of the magnetic levitation. The problem to be solved is to ensure the integrity of the magnetic levitation navigation system by means of essential integration into its structure of the diagnostic subsystem, the basis of which is the phase ranging method. It has been established that the diagnostic procedure for determining the operability of the navigation system of a high-speed vehicle in real time is fully ensured by the use of the phase ranging method. A method of continuous precision positioning of a high-speed magnetic levitation vehicle based on the phase ranging method for an arbitrary configuration in three-dimensional space of a fixed track structure, as well as a method of ensuring the integrity of the navigation system of a maglev train, has been substantiated. A new approach to solving the location problem is proposed, which allows using the train communication channel with the traffic control center as a distributed location sensor as an integral element of the radio wave information and control system. The structure of the information packet cycle is proposed. The volume of the information flow and the degree of redundancy introduced into the information flow to ensure the required reliability of information transmission are determined. The developed diagnostic procedure meets the requirements for the safety and reliability of operation of high-speed ground transport based on magnetic levitation technology, the movement of which is controlled using a navigation system topologically connected with the configuration of the track structure.
Development of a Method of Calculating the Temperature of a Survey Assembly When Preparing a Train Dispatch
(Львовский политехнический национальный университет, Львів, 2020) Ustymenko, Dmytro V.; Kuznetsov, Vitaliy; Marenych, Oksana L.; Kovzel, Maksim; Mukha, Andrii M.; Sinkevych, Oleksiy; Tryputen, Mykola; Al Said Ahmad, Mohammad Ahmad Diab
ENG: The features of the thermal state of the current collection unit «contact wire – contact insert of the current collector» in the conditions of preparation of electric rolling stock for the journey are considered. As part of the study, a methodology has been developed for estimating the heating temperature of the power sliding contact zone in the conditions of train preparation for journey. Application of the method will help to reduce the number of «burnouts» of the contact wire due to the exact selection of the heating/cooling time of the train for a certain heating/conditioning current when preparing the electric rolling stock for the journey. It was established that the cause of the «burns» of the contact wire in the parking lots when preparing the train dispatch is the excess of the permissible temperature of the power sliding contact as a result of the prolonged action of the heating/conditioning current. The standard approach for determining the duration of heating is based on the average values of the loads on the system and therefore does not take into account some factors, for example, the state of the contact wire, the state of the contact insert of the current collector, the number of cars in the train, and so on. The proposed technique is based on the classical theory of electrical contact and the theory of heating a homogeneous body, which makes it possible to accurately assess the thermal state of the power sliding contact and convenient enough for use in operating conditions. The results of the work are of practical value, since the technology of preparing a train for dispatch can be supplemented by calculating the contact temperature «contact wire element – contact insert element» in accordance with the proposed methodology. This will allow for a specific train in specific conditions to apply a set of measures to prevent «burnout» of the contact wire in the event of a possible temperature exceeding the permissible value.
Development of a Spectral Theory for Analysis of Non-Stationary Pulse Stochastic Electromagnetic Processes in Devices of Electric Transport Systems
(National Technical University of Ukraine "Igor Sikorsky Kiev Polytechnic Institute", Kiev, 2019) Szeląg, Adam; Kostin, Mykola O.; Nikitenko, Anatolii; Mishchenko, Tetiana; Jefimowski, Włodzimierz
ENG: A spectral analysis of traction voltages and currents is a basis for estimation of electromagnetic compatibility level and quality of consumed power in electric transport systems. However, such an analysis is usually performed for steady-state modes and only under the condition that the time realization of voltages and currents, being deterministic for continuous quantities, have infinite length. De facto, the electric transport devices operate in non-stationary dynamic modes (starting up, coasting, acceleration, iregenerative braking, stopping, wheel spin, voltage surges, etc.). As a result, the voltage across the traction motors and the current flowing through them are noncontinuous pulsed stochastic processes. It is necessary to add that in emergency modes the voltage and current are short-term single pulses.The paper presents the spectral analysis of such random sequences of pulses as well as their fronts and decays, the concepts of actual and instantaneousspectra. The analytical expressions for amplitudes and the initial phases of k-th harmonics are obtained using the discrete Fourier transformation. The numerical calculations of the spectral composition of stochastic pulse processes of voltage and current were performed for the DE1 and VL8 electric locomotives (Ukraine) as well as for trams operating on the i routes of the city of Dnipro. The actual and instantaneous spectra, as well as the spectra of the full correlation functions and their “tails”, were determined for the electric traction voltages and currents.
Dispersive-Frequency Companding of Low-Frequency Finite Signals for Objects Remote Control
(Национальный технический университет Украины "Киевский политехнический институт", Украина, 2014) Tunik, Vladimir F.
EN: There are noted specificities of known methods of frequency companding of radio signal by high frequency (HF) dispersive delay lines (DDL). It is proposed a principle of dispersive-frequency companding of low-frequency (LF) finite signals for remote control of physical objects and its realization system. It is shown that LF DDL of definite order can be both frequency compressor and frequency expander. The system of this principle realization at transmitting side contains LF DDL - frequency compressor and low-pass filter, and at transmitting side it contains LFDDLof the same order - frequency expander. © Allerton Press, Inc., 2014.
Electrodynamics of Electric Power Transmission and Losses in Devices of Electric Transport Systems
(2018) Kostin, Mykola O.
ENG: For the first time, the "field" approach for explaining the processes of transmission and generation of electric power losses in devices of electric transport systems is described and theoretically substantiated on the basis of the theory of electromagnetic field. The results of the solution of the system of electromagnetic field equations show that it is energetically appropriate to design low-floor types of electric rolling stock. A qualitative view of electric power flows arriving through the air of the feeder zone from the traction substation and entering to the electric rolling stock through the roof and the front part of its body is presented. It is established that the main flow of energy enters through the roof porcelain insulator. At the same time, the electromagnetic waves partly penetrate into the metal surfaces of roof and frontal part of the body, and partially they are reflected from them creating losses of active power. The results of calculations of these losses, power factor and reactive power factor of the electric locomotive roof are shown. The relation between the standing waves, formed in the feeder zone, and the reactive power consumed by the electric rolling stock is established.
Electrodynamics of Power Losses in the Devices of Inter-Substation Zones of AC Electric Traction Systems
(MDPI, Basel, Switzerland, 2022) Nikitenko, Anatolii V.; Kostin, Mykola O.; Mishchenko, Tatyana M.; Hoholyuk, Oksana
ENG: This article presents a new method for the estimation of active power losses based on a “field” approach, i.e., on the theory of the electromagnetic field and the theory of propagation of electromagnetic waves in a dielectric medium. Electromagnetic waves are assumed to transmit energy from the traction substation to electric rolling stock through the airspace of the inter-substation zone (i.e., not through the wires of the traction network) and meet electrically conductive surfaces on their way. The waves are partially reflected from the surfaces and partially penetrate them, thus creating thermal losses, the determination of which is the main task of this article. The analytical expressions for specific losses of active power are obtained by solving the system of Maxwell’s equations. Calculations of specific power losses in the catenary, rails, roofs, and bottoms of carriages and electric locomotives are performed. Power losses in carriages and electric locomotives are found to be at least 7%. A comparative assessment of the magnitude of total power losses of different types obtained by the “field” and “circuit” approaches is provided, which has established that “conditional” losses correspond to losses in rails, train carriages, and electric locomotives.
Electrodynamics of Reactive Power in the Space of Inter-Substation Zones of AC Electrified Railway Line
(MDPI, 2021) Kostin, Mykola O.; Nikitenko, Anatolii V.; Mishchenko, Tatyana M.; Shumikhina, Lyudmila
ENG: In railway traction, the deﬁnition of “electromagnetic ﬁeld” is functionally connected to the concept of the reactive power consumed by the electric rolling stock, and characterized by the running and standing electromagnetic waves in the space of the inter-substation zones from the site of the AC traction system. Such a deﬁnition is established and theoretically justiﬁed by the theory of electromagnetic ﬁelds. This article uses the methodology of this theory, in particular, a method for power balance estimation in electromagnetic ﬁelds based on Maxwell’s equations, as well as methods for the analysis of running and standing electromagnetic waves based on the theory of reﬂection, propagation and transmission of plane harmonic waves. The research considers the regularities of standing electromagnetic waves in the space of inter-substation zones of electric traction systems, which occur due to the incomplete reﬂection of incident waves from the contact wire and metal parts of the roof surface and the frontal part of the body of the electric rolling stock. The ﬂow of electricity to the roof surface and the frontal part of the body of an electric locomotive is considered. The possibility of using existing methods to reduce wave reﬂections and thereby to effectively compensate for reactive power in the space of inter-substation zones is discussed.
Energy of Starting up to Speed of Dc Train
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2015) Kostin, Mykola O.; Nikitenko, Anatolii V.
ENG: In the last 20 ... 25 years the volume of recuperated electric energy is less than 2% of the consumed by traction, while it is possible to return about 10 ... 15%. The main reason is unsatisfactory and inefficient usage of recuperated and transmitted energy to the power supply system. The paper proposes to solve this problem and induce the efficiency and the degree of recuperated energy of DC multiple unit trains by the usage of onboard supercapacitive storage system. The methods of the electric traction theory and the theory of pulse electrical engineering are used for the problem solving. The developed methodology allows to calculate the energy, which is required to starting up the multiple unit train EPL2T to some speed 10 ... 80 km/h after its stopping.Furthermore, the capacity of the on-board storage is calculated in two cases of storing recuperated energy. The novelty of the paper is the new method for estimating energy, which is required to starting up (after the stopping) the train to a certain speed. The analytical expression of the capacity of the on-board storage system was achieved and calculated for the previously estimated energy. For the first time it was found that the energy, which was saved by the on-board supercapacitive storage system, is sufficient to start up the train to some speed and reach the characteristic of full field of the traction motors. The proposed autonomous mode of recuperative braking allows, at first, to increase significantly the efficiency of energy recovery, and secondly, to reduce the weight and size parameters of on-board storage supercapacitors.
Energy Saving During Operation of Equipment with Non-Controlled Electric Drive in Locomotive Depot
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2016) Dubynets, Leonid V.; Marenych, Oksana L.; Baliichuk, Oleksii Yu.; Kortohus, A. S.
ENG: Purpose. To conduct research of electric motors in order to obtain the results that will assess the degree of energy saving due to electric loss reduction in the equipment with non-controlled electric drive. Methodology. The paper proposes an engineering method for determination of active power losses in the motors of the equipment with non-controlled electric drive in locomotive depot during load changes on the motor shaft. It is necessary to analyse the reduction of active power losses in the motor and the power supply network when an under-loaded motor is replaced with a motor having less power. Findings. After the calculations performed by the authors, it was found that for electric motors, in case of reducing the load factor from 0,7...0,75 to 0,4...0,5 active loss reduction after the motor replacement for the less powerful one ranges from 0.58 kW to 2.865 kW. Also, the calculations were carried out on the example of electric motors with a lower synchronous speed, the effect of under-loaded motor replacement increases in terms of active power loss reduction. The greatest effect is achieved when the load factor is kl ≤ 0.55 . Originality. For the first time the paper outlines the issues of energy saving efficiency for the equipment with noncontrolled electric drive in locomotive depot by replacing the under-loaded motors with the less powerful ones. As long as there is a significant amount of the considered electric drives, it may cause severe losses, taking into account the peculiarities of their operation. Practical value. The obtained research results allow us to solve the problem of replacement of under-loaded motors in locomotive depot equipment with the motors having less power as efficiently as possible in terms of reducing electric losses. For instance 90-kW motor of a washing machine can be replaced with 75-kW motor when the load factor is kl ≤ 0.7 , this can significantly reduce the performance losses. This method can be applied not only in locomotive depot but also for all equipment with non-controlled electric drives that operates in under-load mode.
Experimental Investigation of Actual Stuation of using and Accounting of Recovered Energy of Regenerative Braking Mode at the DC Traction System
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Bondar, Oleh I.; Ustymenko, Dmytro V.; Kurylenko, Olena Ya.; Kedria, Mykhailo M.; Karzova, Oksana O.; Krasnov, Roman V.; Baliichuk, Oleksii Yu.
ENG: Abstract. This paper deals with the problems of enhancement of registration and distribution of electric energy which can be obtained from DC electric locomotives by the regenerative braking. According to theoretical researches, it is possible to return approximately 8 - 12% of electric energy which is consumed for electric traction by using of a regenerative braking mode. However in recent years for electric traction networks of JSC “Ukrainian Railways”, this index doesn't exceed 2.6%. So we consider that the regenerative braking is one of the most prospective ways for energy saving in electric railway transport. Results of the experimental researches which were executed on DC traction substations and VL11M6 electric locomotives are described in this paper. Instantaneous values of voltage and current in different modes have been obtained. The electric energy balance for experimental zone has been performed. Also the ways of distribution and consumption of energy of regenerative braking mode have been analyzed. On this basis of the executed investigations, recommendations about providing of supercapacitor energy storage system for Ukrainian railways are proposed.
Feasibility Study for Extending the Rolling Stock Component Life
(Academic Society of Michal Baludansky, Kosice, 2019) Artemchuk, Viktor V.; Krasnov, Roman V.; Karasev, Oleksandr P.
ENG: The article deals with the problem of determining the rational extension of the railway rolling stock component life. It is noted that a key part of the repair development, including on railway transport, is an extended service life of the rolling stock components. Given that a significant proportion of the repair cost is spent for the replacement or repair of worn parts, there is a conclusion that component life must be extended to reduce further repair costs. However, unjustified increase in the service life of all components is not feasible, since the life of individual components may be greater than the life of the entire product. Obviously, it is not expedient to extend the life for all the details, but only that of the most responsible and (or) most worn out, which greatly affect the service life of the assembly or unit as a whole. That is, there is a need to match the life of the entire assembly and individual components. Therefore, in the presented work, theoretical research was carried out to solve the complex task of determining the rational life of rolling stock components taking into account the resource of assemblies and the rolling stock vehicle as a whole. When searching for rational parameters, the durability of components and the factors affecting their life were investigated and the possibilities of various restorative and strengthening technologies were evaluated. The developed approach is flexible and allows for consideration of technological limitations of production, financial constraints and the introduction of life limits for a specific component. Also the article covers the shortcomings of the presented methodology. At the same time it is should be noted that with the development of the diagnostic system, obtaining the necessary data will be less labour intensive and will require less time, and with the development of the necessary software, the accumulation and processing of statistics can be fully automated. In this paper, it is assumed that the presented methodology will make it more attractive to use renewable technologies, save considerable resources and find the necessary restorative or strengthening technology that will bring the life of different components closer to the life of the assembly or mechanism as a whole.
Fryze Reactive Power in Electric Transport Systems with Stochastic Voltages and Currents
(2020) Kostin, Mykola O.; Mishchenko, Tetiana; Hoholyuk, Oksana
ENG: The paper presents the theoretical foundations of reactive power and additional power losses in a direct current electric transport system. Numerical calculations of inactive power and losses in the circuits of electric DC locomotives and trams have been carried out. Discrepancy between the sign of the instantaneous power and the presence of exchange processes in non-linear circuits of electric transport systems with stochastic voltages and currents is discussed.
Fryze Reactive Power of Trams in Eeffective Stochastic Rrecuperation Processes
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Bondar, Oleh I.; Kostin, Mykola O.; Mukha, Andrei; Sheikina, Olha H.; Levytska, Svitlana І.
ENG: Abstract. Urban electric transport system, particularly tram systems, is not a direct current system not only in traction mode but in regenerative modes as both voltage on a collector and regenerative current are stochastic abruptly variable processes. The above- mentioned facts determine availability of Fryze’s reactive power in this system that flows from a railway substation to trams, leads to incidental losses of energy and significantly reduces its quality. So evaluation of power effectiveness of the system in electrical trams operation is impossible without determining the level of reactive power in this system. We have analytical expression of reactive power by Fryze. Numerical calculations for trams type T3D and T4D in regenerative braking modes are done. Probabilistic statistical data processing operation of reactive power expressions is done. It is determined that reactive power changes in the limit of 10…100 kilo-volt ampere reactive with mathematical expectation – 37,0 kilo-volt ampere reactive. Statistical allocation of random power values are different. Numerical calculations of incidental losses, energy of recuperation are done and they range supplementary – 20% from total losses. It is stated that coefficient of reactive power of system route of trams is exceeding permissible value 0,25.
Identification of the Characteristics of Control Signal Generation for Implementing the Traction Mode of a Physical Model of Magnetic Levitation Transport
(ПП «Технологічний Центр», Харків, Україна, 2026) Chupryna, Yehor; Mukha, Andrii M.; Plaksin, Serhii; Ustymenko, Dmytro V.; Bondar, Oleh I.; Marenych, Oksana L.; Holota, Oleksandr; Antoniuk, Andrii
ENG: The object of this research is the process of generating control signals for implementing the traction mode of a physical model of a magnetic levitation transport system. The problem that was solved was the formation of control signals for implementing the traction mode of the physical model and the method of switching track coils. In the experimental physical model, the traction mode is implemented by control signals formed on the basis of the angular values of the encoder corresponding to the position of the crew. Based on these signals, the traction modules of the stand are commutated to ensure the necessary polarity of the magnetic field, which creates traction force and ensures the movement of the crew past the section. The implementation of the traction mode requires accurate determination of the position of the crew relative to the track structure. For this purpose, an encoder signal is used, the information from which is processed in the control unit of the track structure section. A schematic solution and an algorithm for the operation of this unit for a physical model are proposed. The search for an element base for control boards requires performance verification. From several variations of boards, the one that implements the proposed algorithm with satisfactory process quality was selected. The main research method is an experiment conducted on a physical model stand. A switching control unit for the traction section of the physical model stand has been developed and implemented, which includes: control boards, a motherboard and software on the Arduino platform. A board option with three DC-DC converters was selected, which ensured stable operation of the traction section. The main characteristics of electrodynamic processes were obtained, namely: moments of polarity switching of modules, changes in voltage, current and power during the passage of the crew past the section. The switching range of the traction section is approximately five seconds. The results obtained create the prerequisites for the development of experimental stands and models of maglev transport for further research into traction modes.
The Impact of Connecting a Wind Power Plant on Emergency Modes of a Traction Substation of an AC Traction System
(Springer, Cham, 2022) Kachan, Yurii; Kuznetsov, Vitaliy V.; Bondar, Oleh I.
ENG: Among the countries of South-Eastern Europe, Ukraine has the greatest technical potential for the implementation of renewable energy sources, and the main part of it is wind power engineering. The traction power supply system of the railways in Ukraine can become an important transiter and consumer of electricity generated by wind power plants. At the same time, the task of ensuring traffic safety and uninterrupted power supply of traction loads requires a preliminary study of the influence of the connected wind power plant capacity on the growing short-circuit currents in the distributive units of the traction substation to which the specified connection is planned. This paper proposes a way to implement such prediction based on a systematic approach, in which a traction substation and an integrated wind power plant are considered as a single electrical-engineering complex, the sources of which work to power the short-circuit point. In previously published studies, the authors usually consider the processes in renewable energy sources and in the traction power supply system separately, without taking into account the mutual influence. The analysis of processes in the short-circuit mode is proposed to perform according to the equivalent circuits for the specified electrical-engineering complex developed by the authors with various possible options for connecting a wind power plant using mathematical modeling with proven methods of theoretical electrical engineering. The peculiarity of the study presented in this paper is also the use of the multiplication factor of the short-circuit current as a criterion for assessing the impact of the power of the connected wind power plant on the short-circuit currents of the traction substation. In our opinion, the coefficient applied by us more clearly characterizes the specified influence in comparison with operating values or complex sizes of short-circuit currents.
Improvement of Energy Indicators of Conventional Electric Driving Asynchronous Motors of Non-Standard Technological Equipment at the Enterprises for Repair of Railway Rolling Stock Through the use of Energy-Saving Motors
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Bondar, Oleh I.; Baliichuk, Oleksii Yu.; Karzova, Oksana O.; Krasnov, Roman V.; Marenych, Oksana L.; Ustimenko, Dmytro
ENG: Abstract. The purpose of this work is to study the utilization efficiency of electric driving energy-saving motors of non-standard technological equipment meant for repair of railway rolling stock, in terms of improvement of energy performance, i.e. improvement of efficiency factors and power factors, and decrease of power losses as compared with the most commonly used “conventional” asynchronous motors. There are two options for improvement of the energy performance of electric drives of non-standard technological equipment: replacement of a conventional motor with an energy-saving one similar in terms of nominal voltage, rotational speed, power, etc.; changeover of stator winding from “delta” to “star”. A special technique has been proposed to determine the effectiveness of this changeover in terms of improvement of energy indicators. Comparison of the real values of the energy indicators of conventional motors and energy-saving motors in the case under consideration is required to perform the technical and economic calculations when solving the problem of the expediency of replacement of conventional asynchronous motors with energy-saving motors in the abovementioned equipment.
Inactive Power in Electric-Traction DC Transport Systems
(Revijo izdaja Elektrotehniška zveza Slovenije, 2022) Kostin, Mykola O.; Mishchenko, Tetiana; Hoholyuk, Oksana
ENG: The paper presents a theoretical background to determine the inactive power consumption features, i.e. the reactive power according to S. Fryze approach of the electric transport systems. Traction electric circuits of transport facilities of electric locomotives, feeder traction substations and city trams used in Ukraine demonstrate three features of the reactive power. According to the classical method, the inequality between the active and total power indicates the presence of the reactive power. The second feature is the time variation of an instantaneous impedance or instantaneous conductivity. The third is the inequality between the instantaneous reactive power to zero and the nature of its sign throughout the time of the electric power system consumption. The reactive power consumption gives rise to considerable additional power losses in the electric traction transport systems.
Influence of Contactor Contact Pressure in Power Circuits of Electric Stock on their Plastic Deformation and Fusing
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2017) Baliichuk, Oleksii Yu.; Dubynets, Leonid V.; Marenych, Oksana L.; Ustymenko, Dmytro V.
ENG: Purpose. The work is aimed at conducting the study to obtain the results that will quantify the influence of contactor contact pressure in power circuits of electric stock on the highest current value d I , that does not cause plastic deformation of contacts; and on the current value fs I – incipient fusion of contacts taking into account the operation conditions. Therefore, such a study targeted to establish the contact fusing causes is relevant. Methodology. The paper proposes an engineering method for determining the currents d I and fs I , taking into account the value of contact pressure, electrodynamic forces of contact repulsion e.d.r F , as well as the pressure influence on the values of such forces. Findings. Taking the contactors 1SVAD8 (locomotive ChS8) and 7SP1 (locomotive ChS4) as an example, the authors conducted the calculations and found that the peak pressure force increases the currents d I and fs I for these contactors by 11.8%; 15.5%; 11.8%; and 15.4% respectively (compared with the specified currents at the minimum pressure force). Influenced by e.d.r F the pressure force of contacts for 1SVAD8 contactor decreased by 13.8…31.8%, and for 7SP1contactor the value e.d.r F may be greater than the pressure force. This can lead to spontaneous shutdown of the closed contactor that is not provided by the control circuit. Ensuring during operation the maximum allowable pressure force of the contacts c F slightly affects the value e.d.r F, compared with the case when c F has the minimum permissible value (in event of a fault in the heating circuit e.d.r F for contactors 1SVAD8 and 7SP1 is reduced by only 2.45% and 2.59% respectively). Originality. The authors for the first time presented a quantitative assessment of influence of contactor contact pressure in power circuits of electric stock on their plastic deformation and fusing using the proposed engineering method. Practical value. The results obtained during the research allow solving the problem for developing measures aimed to improve the reliability of the heating circuits of electric locomotives ChS8 and ChS4. The proposed method of determining d I and fs I can be used to quantify the influence of pressure of the main electric contacts mounted in power circuits of electric stock of all series, if during the operation there are cases of plastic deformation, fusing, welding of such contacts, in order to improve the reliability of power circuits.
Influence of Feeding Electric Energy Quality on Heating of the Auxiliary Machines of ac Electric Rolling Stock
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2014) Baliychuk, Oleksii Yu.; Dubynets, Leonid V.; Dukhnovskyi, Oleksii M.; Marenych, Olexandra O.; Marenych, Oksana L.
ENG: Purpose. The article aims to study the problem of increase the reliability of auxiliary machines for AC electric trains during operation in real conditions. Methodology. The peculiarity of system construction of auxiliary machines for AC electric rolling stock is the use of asynchronous motors for general industrial purpose. An engineering method of influence determination on the feeding voltage asymmetry and its deviation from the nominal value on heating of auxiliary machines insulation was proposed. Findings. It is found out that in case when the auxiliary machines of AC electric trains work under asymmetry factor of the voltage 10% or more and feeding voltage deviation from the nominal order 0.6 relative unit then it is possible the overheat of their isolation, even if it has class H. Originality. For the first time the issue of the total insulation heating under such boundary parameters combinations of energy quality, when each of them contributes to the heating insulation increase as compared to the nominal regime of the "rotating phase splitter−auxiliary machinery" system was illuminated. Practical value. Conducted research allow us to establish the boundary parameter values of feeding energy quality (asymmetry factor, feeding voltage deviations from the nominal value), at which additional isolation overheating of this class under the effect of specified factors will not exceed the agreed value.
Instantaneous Reactive Power in Systems with Stochastic Electric Power Processes
(National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute, 2019) Nikitenko, Anatolii; Kostin, Mykola O.; Szeląg, Adam; Jefimowski, Włodzimierz; Mishchenko, Tetiana
ENG: The paper is dedicated to the estimation of instantaneous reactive power in a DC traction power system. Currently, the integral and frequency methods are mostly used to define reactive power and do not give high accuracy in the calculations of power balance or cannot describe the essence of physical processes.The problem is complicated in DC electric transport systems due to random impulse character of voltages and currents. As a comparison, the calculation of reactive power according to various approaches was performed for the DE1 electric locomotive. It is suggested that the instantaneous reactive power should be used for the analysis of electromagnetic exchange processes in DC power systems. The paper shows the definition and main formulas for defining the instantaneous reactive power taking into consideration the random character of voltage and current. Numerical calculations together with statistical analysis were performed for two variants of experimentally recorded voltages and currents: the first one – on the bus-bar of traction substation, which supplies the section with the Pendolino trains in Poland and the second one – on the current collector of the VL8 electric locomotive in Ukraine. They confirm the validity of the aforementioned method.
Losses of Recovered Electric Energy in the Elements of a DC Electric Transport System
(IEEE, 2016) Szelag, Adam; Kostin, Mykola O.; Nikitenko, Anatolii V.
ENG: The regenerative braking is one of the most attractive ways for energy saving in electric transport. It has many advantages and its effectiveness is discussed in numerous researches, but there are no significant publications, which describe the power losses in the way of recovered current flowing. The paper describes an alternative method for estimating recovered energy losses in the elements of a DC electric transport system. In comparison with existing methods, it is based on the correlation theory of stochastic processes and takes into account the Fryze’s concept for reactive power. The method is verified by the experimental researches, which are performed for the VL8, VL11M, VL11M6 locomotives, EPL2T multiple-unit train and T4D tram, which operate in DC sections, Ukraine. The losses are calculated for different elements of an electric transport system, and their theoretical and statistical distributions with basic probabilistic characteristics are shown. The results prove the validity and applicability of the method.
Methods of Spectral Analysis of Traction Voltages and Currents as Random Functions
(IEEE, Lviv, 2015) Nikitenko, Anatolii V.
EN: The paper shows the methods of spectral analysis of stochastic traction voltages and currents. The results of analysis are shown for the voltage, which was recorded in the process of real operation of EPL2T electric multiple-unit train.
Modeling of Electromagnetic Processes in a Nonlinear Circuit of an Electrolyzer for Pulse Deposition of Metal Coatings
(Український державний університет науки і технологій, ННІ «Дніпровський металургійний інститут», ІВК ≪Системні технології≫, Дніпро, 2025) Bondar, Oleh I.; Siversky, Serhii; Gurin, Yevgen; Koliadenko, Oleksandr; Bashko, Volodymyr; Kopysov, Vladyslav; Pilipenko, Vyacheslav
ENG: The primary objective of this study is to construct a comprehensive analytical model describing the electromagnetic processes in a nonlinear electrical circuit of an electrolyzer operating under pulsed electrodeposition conditions. Special attention is given to the influence of reversed rectangular voltage pulse parameters on the near-cathode voltage drop, deposition current, and the general electrochemical behavior of the system. The goal is to identify optimal operation modes of the pulse power supply that ensure high-quality metal coatings while minimizing energy consumption and structural defects. Methodology. The research employs the method of variable transformation to develop a set of differential equations describing the dynamic behavior of voltage and current in a nonlinear electrolyzer circuit during pulsed operation. The model accounts for critical circuit components: resistive, capacitive, and inductive elements of the electrolyte, as well as nonlinear conductances reflecting electrochemical properties. Analytical expressions for voltage drop and deposition current are derived for both the forward and reverse pulse intervals. The model includes the influence of electrolyte inductance–an often-neglected factor–which significantly alters the current front shape and ultimately affects deposition kinetics and coating characteristics. Numerical simulations are performed to validate the analytical solutions. Results. Closed-form analytical expressions were obtained for the time-dependent near-cathode voltage drop and deposition current under pulsed conditions. It was shown that the electrolyte inductance leads to a rounding of the current front, influencing both the amplitude and stability of the electrochemical reactions. A parametric analysis identified that the optimal pulse duty cycle lies in the range of τ/T ≈ 0.73 to 0.78. Within this interval, the maximum near-cathode voltage drop does not exceed 0.6 V, while the peak voltage and total current remain within safe technological limits (up to 13 V and 150 A, respectively). The average partial discharge current at the cathode remains stable at approximately 70 A, ensuring consistent deposition rates. Scientific novelty. This work introduces a novel analytical approach to modeling pulsed electrodeposition that, for the first time, includes the effect of electrolyte inductance. Unlike existing models relying heavily on numerical simulations, the proposed model allows for direct computation of key process parameters. It enables the derivation of precise criteria for determining the optimal ranges of input pulse parameters–both in amplitude and duration–necessary to avoid the formation of crystalline defects and to achieve uniform, high-quality coatings. These innovations significantly advance the theoretical understanding of pulsed electrochemical processes. Practical significance. The developed model provides a valuable tool for industries that utilize electrochemical metal deposition, including microelectronics, galvanics, mechanical engineering, and power systems. It offers a foundation for designing advanced pulse power supplies with optimized operation modes and supports the development of automated control systems for deposition processes. Furthermore, the model can aid in adapting laboratory results for industrial implementation, improving coating quality, process efficiency, and operational reliability.
Modeling of Wind Speed Distribution in Urban Environment for the Application of Wind Energy Potential Estimation: Case Study
(UIKTEN, Serbia, 2025) Mykhailenko, Oleksii; Karabut, Nadezhda; Doskoch, Volodymyr; Burtseva, Olena; Kuznetsov, Vitaliy V.; Tsvirkun, Sergij; Kolomits, Hanna
ENG: When designing wind farms, the first stage is always an assessment of the target area wind energy potential. It is necessary to have a mathematical description of the wind speeds occurrence probability at the wind turbines potential location to do this. An analysis of relevant studies shows that the most effective approach to obtaining such dependencies is when the wind speed is taken as a random variable. In this case, wind speed distribution in the target area can be modeled using continuous probability distributions. This article is devoted to determining the typical probability distribution models for representing wind conditions in certain areas of the Dnipropetrovsk oblast (Ukraine), which can be used to estimate expected level of power generation by wind power plants. To obtain the data, a series of wind speed measurements were taken at three locations throughout the year. After that, frequency wind speed distributions with ranges of 0.2, 0.5, and 0.8 m/s were created from the obtained dataset and then approximated by continuous probability distributions. Frequency distributions were modeled by Weibull, Rayleigh, Nakagami, gamma, normal, log-normal, generalized extreme value, Birnbaum-Saunders, Wald and Rice continuous distributions. To determine the parameters of each type probability distribution, which is the most relevant to the frequency distribution, the maximum likelihood estimation method was used. To assess the accuracy of the models, the Pearson test, coefficient of determination and normalized root mean square deviation are used. The probability distributions quality is also evaluated graphically using Q-Q plots. The best fit to wind speed frequency distributions demonstrated by the Weibull probability distributions. A slightly lower accuracy was provided by the normal, Rice and Nakagami distributions than Weibull distribution. But in some cases, these distributions have even smaller error than the last one. Therefore, after detailed analysis and validation, they can also be used. The Rayleigh distribution had the worst accuracy, the Pearson test for it rejected the null hypothesis that the probability distributions correspond to the frequency distributions at all three locations. Additionally, the effect of the frequency distribution wind speed grouping range on the quality of maximum likelihood estimation of continuous distribution parameters was analyzed. It showed that the approximation accuracy decreases with increasing range.
Nanostructures in the Formation of the Properties of High-Current Sliding Electrical Contacts on the Electric Rolling Stock
(Igor Sikorsky Kyiv Polytechnic Institute, 2019) Ustymenko, Dmytro V.; Mukha, Andrii M.; Baliichuk, Oleksii Yu.; Kurylenko, Olena Ya.; Romanov, Serhii; Sabiev, Tamerlan
ENG: The paper presents the results of bench tests of wear resistance of contact inserts of current collector runners made of «ROMANIT-UVLSh» material and their effect on the wear of the copper contact wire is evaluated. This material is a composite with a high content of electrically conductive lubricants capable of forming a thin conductive transition layer in a friction pair. Low temperature in the contact zone, indirectly, indicates a low transition resistance and high energy performance of the sliding contact, and low wear of the contact wire confirms its high tribological and mechanical properties. The use of contact inserts runner’s current collectors made from this material is possible, both in alternating and direct current and can provide higher technical and economic indicators in comparison with traditional materials.
Physico-Technological Aspects of Work of Lubricant Films in the Tribosystem «Overhead Line-Current Collector Contact Sstrip»
(Дніпропетровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2018) Ustymenko, Dmytro V.
ENG: Purpose. The article aimed at comprehensive analysis of the processes occurring in the lubricant films of the friction surfaces of the tribosystem «overhead line – current collector contact strip» (OLCCCS) and identification of the features of such systems. Methodology. The systematic analysis was used as the main methodology for studying the physico-technological aspects of work of the lubricant films in the tribosystem «overhead line – current collector contact strip». Findings. The theory of electro-friction interaction is now at such a stage that is characterized by a large amount of accumulated empirical data, hypotheses and models that cannot adequately represent phenomena in a sliding, high-current electrical contact. The sliding electrical contact of the tribosystem «overhead line – current collector contact strip» during the operation is affected by many factors, one of which is the processes in the lubricating layers of the friction pair. The work leads to a new level of understanding of the peculiarities of the processes occurring in the lubricating layers and their effect on the work of a sliding, high-current electrical contact, which can become the guarantee of significant increase in the efficiency of such systems and, as a consequence, substantially increase the reliability and safety of the work of the electric stock. Originality. It is proposed to consider the processes of electro-friction interaction of electrical contacts from the position of synergy using the theory of fractals as the core one for the quantitative description of self-organizing structures. Practical value. Taking into account the empirical experience of operation of the tribosystem «overhead line – current collector contact strip» in combination with theoretical knowledge allows us to propose three possible directions for solving tribological problems in high-current sliding electrical contacts. They are: 1) change in contact geometry and surface topography, for example, the use of regular macrorelief of contact surfaces; 2) development of conductive composites which are characterised with self-lubrication, for example the use of composite materials containing solid conductive lubricants; 3) devel-opment of effective lubricants for electric high-current sliding contacts, which may require some complication of the component design.
The Principle of Creating a «Smart» Electricity Meter in Electric Traction Networks with Stochastic Electromagnetic Processes
(Lviv Polytechnic National University, Lviv, Ukraine, 2021) Kostin, Mykola O.; Mischenko, Tetyana; Hoholyuk, Oksana
ENG: Voltage and current are sharply variable random (stochastic) processes in traction networks of DC electric transport systems. As a result, electronic and hybrid electricity meters used in electric systems measure electric power with a large relative error that significantly exceeds that of their accuracy class. In this paper the principle of developing smart meters for accounting the electricity transmitted from traction substations to electric rolling stock through a traction network is proposed. Proposed ideas are developed on the basis of the random processes correlation theory. The meter operates in real time and monitors not a set of realizations of random voltage and current processes, but their deterministic characteristics, that is, time functions of mathematical expectations and variances which make up the background of its operating principle. The experimental implementation of the proposed principle has been conducted in the feeder zone of an A-B section of the GisDnieper Railway of Ukraine, where registration and processing of realizations of stochastic voltage and current processes obtained in real operation mode has been done. The ratios obtained for active and reactive power can be applied not only for traction power grids, but also for electric networks of external power supply of DC electric traction systems as the basis for the “smart meter” design.
Principles of Constructing Equivalent Circuits for Nonlinear Electrochemical Elements: Analysis and Experimental Parameter Determination
(Український державний університет науки і технологій, ННІ ≪Інститут промислових та бізнес технологій≫, ІВК ≪Системні технології≫, Дніпро, 2024) Bondar, Oleh I.; Nikolenko, Anatolii V.; Kovalenko, Viktor; Kitaev, Oleh; Stepanenko, Oleh; Siversky, Serhii; Sprysa, Vasyl
ENG: The paper proposes a generalized scheme for replacing the electrolyzer for the deposition of metal coatings. As nonlinear elements of the specified scheme, the dependences of the partial currents of metal dissolution and deposition on the near-anode or near-cathode voltage drop are considered, respectively. The possibility of applying certain simplifications in the general scheme, depending on the peculiarities of the deposition process of one or another metal, was also analyzed. At the same time, the general structure of approximating expressions is proposed and the approximation coefficients for individual nonlinear electrochemical elements are determined. The specified expressions differ from the previously known ones in that their structure is suitable for obtaining the general regularities of electromagnetic processes that take place in systems of pulse electrodeposition of metals in an explicit form.
Reactive Power Compensation for Non-Traction Railway Consumers
(Institut Kolejnictwa, 2020) Mukha, Andrii M.; Bondar, Oleh I.
ENG: This paper deals with the problems of power supply efficiency for non-traction railway customers. Unlike public distribution networks, the non-traction power supply network is within the zone of influence of electromagnetic fields and the conductive influence of the distorted traction current. As a result, poor power quality and additional losses are typical for non-traction railway networks. Subsequently, conflicts due to the low quality of electricity may arise between the railway and its customers powered by the distribution networks of the railway. The influence of a reactive power compensation device on the voltage drop in a non-traction power line is investigated in the article. The implementation of reactive power compensation allows voltage losses during its transmission to the final consumer to be reduced by almost 5% and electricity losses by 3%.
Reactive Power Compensation for Non-Traction Railway Consumers (preprint)
(Institut Kolejnictwa, 2020) Mukha, Andrii M.; Bondar, Oleh I.
ENG: This paper deals with the problems of power supply efficiency for non-traction railway customers. Unlike public distribution networks, the non-traction power supply network is within the zone of influence of electromagnetic fields and the conductive influence of the distorted traction current. As a result, poor power quality and additional losses are typical for non-traction railway networks. Subsequently, conflicts due to the low quality of electricity may arise between the railway and its customers powered by the distribution networks of the railway. The influence of a reactive power compensation device on the voltage drop in a non-traction power line is investigated in the article. The implementation of reactive power compensation allows voltage losses during its transmission to the final consumer to be reduced by almost 5% and electricity losses by 3%.
Software–Hardware Random Numbers Generating Complex Based on Mobile Device
(CEUR-WS Team, Aachen, Germany, 2025) Shynkarenko, Viktor I.; Ostapets, Denis O.; Opriatnyi, Artur
ENG: The effectiveness of many modern technologies in such fields as statistics analysis, computer games, gambling, testing, computer graphics, simulation, cryptography, information security algorithms and any others depends on the quality of random number generating means. The article represents the development principles of the software – hardware pseudo and true random numbers generating complex based on using a mobile device. An analysis of entropy sources provided by mobile devices is submitted. The accelerometer, gyroscope, and magnetometer sensors of mobile device are chosen as entropy sources. The complex architecture and the TCP - connection based communication protocol between the complex parts have been developed. The total number of considered modes for generating pseudo and true random number sequences is six. The software of server, client and mobile parts of the complex is implemented. Research of pseudo and true random number sequences quality obtained in different modes using a statistical and visual tests suite is submitted. An analysis of the results and a comparison with the previously known ones is performed. Recommendations for using different generating modes are given.
Statistics and Probability Analysis of Voltage on the Pantograph of Dc Electric Locomotive in the Recuperative Mode
(Wydawnictwo SIGMA, 2013) Kostin, Mykola O.; Nikitenko, Anatoliy V.
ENG: The statistical analysis and probability characteristics of voltage random variation on the pantograph of DC electric locomotive in the recuperation mode are presented in the article.
Study of Short Circuit Currents in a Distributed Traction Power Supply System with Renewable Electric Power Sources
(IEEE, 2022) Kuznetsov, Valeriy; Kuznetsov, Vitaliy V.; Bondar, Oleh I.; Rojek, Artur; Hubskyi, Petro V.; Stypulkowski, Piotr
ENG: The problems of changing short-circuit currents in a distributed traction system for using renewable energy sources were analyzed in the article. Literary sources analysis shows a further tendency for increasing the share of renewable energy sources in the total energy balance of the country and a particular increase in electricity consumption by electric traction. Goal. The main goal of the study is a method development with its practical application to impact estimation of power-boost points that connected to the traction network with energy using from renewable sources on short-circuit currents values. Methodology. The method that has developed in this study is based on well-known approaches for equivalent circuits of electrical equipment definition, but elemenst pair like «solar panel - inverter» it reproduces as EMF with equivalent resistance, which significantly simplifies further calculations. Results. The study results show that the application of power-boost points will not lead to a significant increase of short-circuit currents in the traction network even if the power of photovoltaic sources will be comparable with the power of existing converting units on traction substations. This is because of the physical nature of the photovoltaic panel and its power mode which usually closer to the current source with high internal resistance. Practical value. This also allows us to conclude that in most cases from the point of view of changing the short circuit currents the integration of power-boost points that are powered by solar power plants is quite possible with operating sections of the traction power supply system.
Tabulated Sections of Low-Frequency Dispersion Delay Lines on a Basis of Phase Circuits
(Национальный технический университет Украины "Киевский политехнический институт", Украина, 2012) Tunik, Vladimir F.
ENG: There is noted essential importance of known methods of hardware analysis of low-frequency signals spectrum and drawbacks of dispersion delay lines (DDL) for dispersion analysis of such signals, and existent tables of pass-band DDLs do not allow to obtain transfer functions of DDL for low frequencies. There are shown possibilities of containing of tables for such DDLs sections on phase circuits of the first and the second orders. There is proposed new table of main parameters and zeros of Hurwitz polynomials for group delay times of DDL sections of low frequencies 5, 7, 9, 11, 13 and 15 orders, each of them is represented with separate Mathcad document.
Technical Losses of the Recovered Electric Energy in DC Traction Power Supply System
(Національний університет "Львівська політехніка", 2013) Nikitenko, Anatolii V.
EN: The efficiency of the recuperative braking of DC electric rolling stock is analyzed in the article. The monitoring of voltages and currents was done for the trains EPL2T and locomotives VL8 in the traction and the recuperative braking modes. The basic, additional and the total technical losses of the recuperated energy were calculated for DC traction power system. The statistical and theoretical distributions of the RMS current, the additional and total losses were drawn and the basic probabilistic coefficients were calculated for them.
Technical Losses of the Recovered Electric Energy in DC Traction Power Supply System (preprint)
(Національний університет "Львівська політехніка", 2013) Nikitenko, Anatolii V.
EN: The efficiency of the recuperative braking of DC electric rolling stock is analyzed in the article. The monitoring of voltages and currents was done for the trains EPL2T and locomotives VL8 in the traction and the recuperative braking modes. The basic, additional and the total technical losses of the recuperated energy were calculated for DC traction power system. The statistical and theoretical distributions of the RMS current, the additional and total losses were drawn and the basic probabilistic coefficients were calculated for them.