Browsing by Author "Kostin, Mykola O."
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Item 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.Item 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, WłodzimierzENG: 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.Item 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.Item 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, OksanaENG: 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.Item 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, LyudmilaENG: 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.Item 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.Item Fryze Reactive Power in Electric Transport Systems with Stochastic Voltages and Currents(2020) Kostin, Mykola O.; Mishchenko, Tetiana; Hoholyuk, OksanaENG: 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.Item 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.Item Inactive Power in Electric-Traction DC Transport Systems(Revijo izdaja Elektrotehniška zveza Slovenije, 2022) Kostin, Mykola O.; Mishchenko, Tetiana; Hoholyuk, OksanaENG: 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.Item 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, TetianaENG: 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.Item 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.Item 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, OksanaENG: 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.Item 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.Item Transient Stochastic Processes in Power Circuits of Electric Transport Systems(IEEE, 2019) Kostin, Mykola O.; Mishchenko, Tetiana; Liashuk, Vitalii; Hoholyuk, Oksana; Stakhiv, PetroENG: The analytical method for the purpose of analyzing the transient processes occurring in the power traction circuits of DC electric transport systems allowing to take into account existing stochastic character of electric traction voltages and currents has been proposed. The method is based on using a modified form of Duhamel's integral adapted to the theory of random processes, in which the weight function is determined by the solution of the Wiener-Hopf correlation integral equation. Based on relationships of the proposed method the numerical calculations of transient stochastic characteristics (the function of mathematical expectation, the function of correlation, root-mean square deviation and dispersion) of the locomotive current in freight train operation of the Prydniprovsk railway were carried out.