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# Електромагнітна сумісність та безпека на залізничному транспорті

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Науково-практичний журнал "Електромагнітна сумісність та безпека на залізничному транспорті"

Scientific and practical journal "Electromagnetic Compatibility and Safety on Railway Transport"

Scientific and practical journal "Electromagnetic Compatibility and Safety on Railway Transport"

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Item 1-й випуск. Електромагнітна сумісність та безпека на залізничному транспорті(Видання Дніпропетровського національного університету залізничного транспорту, 2011)Show more UK: Розвиток нових систем управління та регулювання рухом на залізничному транспорті, що відбувається останнім часом, в тому числі мікроелектронних і комп’ютерних пристроїв автоматики, цифрових телекомунікаційних систем, імпульсних напівпровідникових силових перетворювачів для живлення тягових та допоміжних пристроїв рухомого складу, зробили ще більш актуальною проблему доведення їх безпеки та електромагнітної сумісності. На великий інтерес до проблеми електромагнітної сумісності у світі вказує велика кількість дослідницьких та випробувальних центрів, що працюють з цієї проблеми, та регулярні симпозіуми і конференції, що провадяться їми. В Україні спеціалізованих журналів з електромагнітної сумісності на залізничному транспорті до сьогодення не було. Вважаю, що випуск такого журналу буде сприяти координації робіт дослідників у цьому напрямку та підвищить безпеку на залізничному транспорті. RU: Происходящее в последнее время развитие новых систем управления и регулирования движением на железнодорожном транспорте, в том числе микроэлектронных и компьютерных устройств автоматики, цифровых телекоммуникационных систем, импульсных полупроводниковых силовых преобразователей для питания тяговых и вспомогательных устройств подвижного состава, сделали еще более актуальной проблему доказательства их безопасности и электромагнитной совместимости. На большой интерес к проблеме электромагнитной совместимости в мире указывает большое количество исследовательских и испытательных центров, работающих по этой проблеме, и проводимые ими регулярные симпозиумы и конференции. В Украине специализированных журналов по электромагнитной совместимости на железнодорожном транспорте до сих пор не было. Полагаю, что выпуск такого журнала будет способствовать координации работы исследователей в этом направлении и повысит безопасность железнодорожного транспорта. EN: Development of a new control and regulations railway movement systems, including microelectronic and computer automatic devices, digital telecommunication systems, pulse semiconductor power converters for a electrosupply of traction and auxiliary rolling stock devices, occurring recently, have made even more actual a problem of the proof of their safety and electromagnetic compatibility. A plenty of the research and test centers working on this problem and regular symposiums and conferences, spend by them, specify on great interest to a problem of electromagnetic compatibility in the world. In Ukraine a special journals on electromagnetic compatibility on railway transportation was not till now. I believe that realization of such journal will promote coordination of work of researchers in this direction and will increase of a railway transport safety.Show more Item The Accuracy of Traction Current Harmonics Parameters Determination by Windowed FFT(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2018) Havryliuk, Volodymyr I.Show more EN: In the work the correct choosing of the windowed FFT parameters to achieve the necessary time and frequency resolution of the traction current spectral analysis in accordance with the re- quirements of regulatory documents has been briefly overviewed and investigations of the influence of FFT parameters on the accuracy of the determination of harmonics parameters (such as effective current, frequency, duration) have been carried out.To assess the accuracy of determining the RMS current and frequency of the harmonics, a computer study was performed using a synthesized current with known harmonics parameters, the values of which were chosen in accordance with the permissible values of the parameters determined by regulatory documents and standards.For the spectral analysis of traction current, four types of windows were selected: rectangular, Hann, Hamming and Blackman windows with duration of 0.3 and 1 s. For a sampling frequency of 27500 Hz and a window length of 0.3 s, the frequency resolution is 0.27 Hz for a rectangular window, 0.54 Hz for Hann and Hamming windows and 0.81 Hz for Blackman's window, which is consistent with the requirements of the specifications.The results of spectral analysis of traction current showed that the frequency resolution of harmonics, and accordingly the relative error in determine the frequency and the RMS value of harmonics is lower for high frequencies in spectrum.The type of windows used has a slight effect on the accuracy of determining the frequency of harmonics. The relative error of the effective value of the harmonic current was higher for a rectangular window, and relative error decreased in the row from the rectangular window to the Blackman window. The values of the relative error of the RMS current for several frequencies ofthe harmonics did not meet the requirements necessary for the practical use of the method, and this is due to spectrum leakage and scalloping.For windows with a length of 1 s, the frequency resolution of the traction current was higher. than for windows with a length of 0.3 s, and the relative error of the RMS current and frequen- cies of the harmonics were much lower, but even in this case, the relative error was high for individual frequencies .To ensure the necessary accuracy of the traction current spectral analysis with using win- dowed FFT, proper choosing of the spectral analysis parameters taking into account the traction current parameters is necessary. Taking into account a wide frequency range of traction current, a technique with variable window length and sampling frequency for different parts of the spectrum is perspective for using.Show more Item Analysis of Operation of Railway Communication Systems(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Botnarevscaia, R.; Serdiuk, Tetiana M.Show more ENG: Actuality. Technological progress, which has rapidly burst into our lives, dictates its own rules. There is a need to modernize the railway infrastructure, which, in its current equipment, built in 70-80 years of the last century, is morally and technically obsolete. Considering the huge volumes of work to be done, we come to the understanding that it is not possible to carry out such modernization in a short time, both from a financial point of view and from a technical point of view. For a long time, you will have to measure with the simultaneous operation of both new and old equipment and ensure their uninterrupted functioning. New electronic equipment introduced in various fields requires careful testing for electromagnetic compatibility. Ensuring safety in the transport of passengers and goods depends on this. So, the scientific work deals with the analysis of operation of railway communication systems are actuality. The object of research is railway communication lines. The main purpose is to evaluate the quality of different kinds of railway communication and the reasons of noise and interference in these systems. It was carried out the follows in the paper: the reasons of appearance noises in the telecommunication channels (radio and wire communications) were analyzed; the main faults in the overhead communication lines and their influence on the quality of communication were evaluated; the electromagnetic interferences in the communication lines and their frequency diapasons were researched; the further ways of investigation and simulation of influence traction and non-traction systems on the communication channels were described. The scientific novelty is in the proposition of use CST simulation to investigate electromagnetic influence of traction and non-traction power system on the communication channels with the 8-poles mathematic modelling. Research will be carried out by the method of direct measurements on existing equipment and collection of statistical data. At the end of the research, conclusions will be drawn about the electromagnetic compatibility of the of old and new equipment of communication systems, and we can say that the issue does not lose its relevance due to the introduction of new types of rolling stock, the modernization of traction substations.Show more Item Automated Measurement of Parameters of Track Circuits(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2015) Serdiuk, Tetiana M.Show more EN: The method of measuring the parameters of track circuits (a time and amplitude parameters of code current, flowing in rail lines, an input impedance of the track circuit, a characteristic impedance, a propagation constant) is considered in this paper. The algorithms of definition of parameters of track circuit (ТС) are elaborated. As a result, the develop hardware-software apparatuses allows you to define by the EMF induced in the two receiving coils separately, the following quantities: the magnitude of the code current for the entire length of the track circuit, the duration of the pulses and pauses for all parcels of code, determine the type of code signal and the type of code track transmitter, coordinate, the length of the TC, serviceability of insulating junctions and electrical connectors. The results of measurements of EMF induced in each of the receiving coils apart, the spectral composition of the noise occurring in the traction network, and harmonic amplitude and impulse noise, the causes of noise in the rail network can be revealed. Algorithm for checking the status of the track circuit involves determining the state of the track circuit and it is carried out on the current curve of the locomotive signalling depending on the coordinates obtained from the measurements. Underestimated the value of ALS current compared with the calculated value indicates an undervalued ballast resistance. The test of offered measuring apparatuses were executed on the Pridneprovsky railway.Show more Item The Comparative Analysis of Calculating Methods for Ac Impedance of R65 Type Rails and Track 1520 Mm Gauge in the Audio Frequency Range(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2017) Havryliuk, Volodymyr I.Show more EN: Knowledge of the exact AC rail impedance in a wide frequency range is necessary for designing and modeling audiofrequency track circuits, determining of the traction return current distribution in rails of high-speed railways, testing new types of vehicles on electromagnetic compatibility with track circuits, etc. The aim of the work is to perform a comparative analysis of the methods for calculating of the AC impedance of the R65 type rails of a track 1520 mm gauge in the audiofrequency range. Results of AC rail impedance measurements and theoretical description of frequency dependence of impedance for wires above lossy ground are briefly reviewed. Mathematical formulation of Carson's method and the complex image method proposed by Deri with co-workers for impedance of transmission lines were represented. The impedance of running rails of R65 type and track of 1520 mm gauge have been calculated by using Carson's method and the complex image method. Due to the insufficient amount of literature data concerning AC impedance measurements for rails of type R65 of 1520 mm gauge, the results of calculations for these rails were compared with the measured values for both rails of type R65, 1520 mm gauge, as well as for rails of type UIC 60 with 1435 mm gauge. Calculated frequency dependencies of the AC impedance of R65 type rails are in good qualitative agreement with literature data for rails UIC60 in frequency range Hz... The results for rails of R65 type and 1520 mm gauge calculated according to Carson's method and complex image method differ from reference data presented in literature, and these differences increase with increasing of frequency. Such behavior may be due to error of calculation methods caused by small height of rails above lossy ground and high electrical conductivity between rails and a ground.Show more Item Comparative Analysis of Experimental and Calculation Methods for Determination of the Traction Current Harmonics Distribution in Rails(Дніпровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2018) Havryliuk, Volodymyr I.; Meleshko, V. V.Show more EN: The purpose of this work is to perform the comparative analysis of experimental and calculation methods for determination of the distribution of traction current harmonics in rails. To investigate the distribution of traction current in the rails, the special marks ("flags") were set up at a certain distance (100, 300 and 500 m) from the point of measurement along the track. The moments of passing the train past the "flags" were recorded in a computer due to a sound signal from the train, as well as visual observation. The train was moving in the measuring section in a quasistationary mode with an average speed of about 48 km/h. Traction current was measured in circuit of the interthrottle jumper with using an inductive contactless sensor and registered using computer. The distribution of the return traction current harmonics in rails for AC feeding systems were modeled by using the multiconductor transmission line (MTL) model. Some discrepancies in the results of experimental and calculation methods were observed. One of main reason of measurement errors were an inaccuracy in determining distances from the train to the measurement point. Calculation errors were related mainly with using inaccurate electrical parameters of track in model, in particular, the track ballast resistance and the ground resistances. However, in general, the considered model can be used for investigation of the traction current harmonic propagation in rails from train, and their influence on the track circuits receivers for different cases including the variation of the track circuits electrical parameters, as well as the number of rolling stock units in the feeder zone. Such analysis of harmonic in rails is important for revealing the causes of failures in railway signalling system operation under simultaneous affecting on it several factors adverse to safe operation.Show more Item The Comparative Analysis of Main Calculation Methods of Matrix Elements' Impedance of 1520 mm Rail Track Gauge in Audio Frequency Range(Днепропетровский национальный университет железнодорожного транспорта имени академика В. Лазаряна, Днепропетровск, 2014) Havryliuk, Vladimir I.; Meleshko, V. V.Show more EN: With the aim of comparative analysis of main calculation methods of series impedance matrix for 1520 mm rail track gauge in audio frequency range a brief mathematical formulation revue of two methods for calculation of traction rails' impedance with consideration of earth return current has been carried out. The applicability of Carson's method and complex depth of earth return method for calculations of impedance of 1520 mm track gauge in frequency range 1005 Hz have been con-firmed. ..10 The observed differences of calculated results and measured data may be eliminated by correct choice of parameters in the calculation formulas.Show more Item Determination of Basic Data for the Six-Polar Model of Electrical Tonal Rail Circuit(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, 2016) Romantsev, Ivan O.Show more EN: Purpose. Development of the model and input data of the six-polar model of electrical tonal rail circuit as an example of the functional units with concentrated parameters. Methodology. For the development of the six-polar model is necessary to form the structure of the object of study, taking into account all the ground resistances of each functional block of electrical tonal rail circuit; form a six-polar model and define the parameters of the rail track filter. Findings. The data make it possible to form a full six-polar model of electrical tonal rail circuit and obtain the necessary dependencies between electrical parameters and current performance of electrical rail circuit. Originality. During the work formed the structure of the six-polar model of electrical tonal rail circuit, method for determining the mathematical model of the six-polar element of electrical tonal rail circuit with concentrated parameters. Practical value. The obtained data will allow optimizing the maintenance costs of the electrical rail circuit and cable network parameters. Further analysis of dependencies will determine the optimal permissible limits of controlled parameters for diagnostics system of railway automation devices.Show more Item Emulation of the Work of the ABS Position of the Pulsewired Automatic Block Signalling of a DC(Дніпровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2018) Romantsev, Ivan O.Show more EN: The principle of automatic block signaling simulation using the example of a pulsewire DC blocking is presented. A simulation of the logical connections of the signal indications of traffic light and their adaptation for the realization of the interaction of one signal point with its neighbors is given. The most frequent system malfunctions are taken into account, their modeling is provided. Selected input and output data, implemented in the Labview, described the interface and block diagram of software.Show more Item Experimental Determination of Basic Data for Probabilistic Research of Electrical Tonal Track Circuit(Дніпропетровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2017) Romantsev, Ivan O.; Havryliuk, Volodymyr I.Show more EN: Purpose. Determination of mathematical model with the probabilistic parameters of tonal-frequency railway circuit, leadthrough of the concomitant measurings and their analysis, forming of maximum sizes of the probabilistic states of object. Methodology. At research of the probabilistic states of railway circuit the terms of measurings of probabilistic descriptions, parameters of transformations of frequency-temporal descriptions of signals are certain, the statistical results of the conducted measurings are analyzed, the table of the probabilistic diagnostic is formed, and the probabilistic scopes of diagnostic of the states of tonal-frequency railway circuit are got. Findings. Determination of scopes of premature exit from working condition state of tonal-frequency railway circuit. Originality. Principle of determination of statistical information is presented for the system of the probabilistic diagnosticating of tonal-frequency railway circuit, laws of distributing of parameters and finding of premature exit state and maximum scopes of electric parameters. Practical value. Findings enable to form the system of the probabilistic diagnosticating of tonal-frequency railway circuit.Show more Item Impact of Electromagnetic Interferences on Traction Network: Mathematical Model of Traction Network(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Taghizade, Ansari Hossein; Serdiuk, Tetiana M.; Mysiv, IvanShow more ENG: In Ukraine, almost half of the railway lines are electrified. In railway network, there are automatic devices by w ich traffic of trains and safety on the railway are regulated. However, there are some faults in these automatic devices that can put the passengers and the railway system’s safety at risk. The main sources of these faults are the presence of the stray currents, harmonics, and the electromagnetic interferences. For investigation of these faults, having an accurate model of the railway network is vital. So the topic of research is actuality now. The main goal of this paper is to study the propagation of traction current harmonics on feeder zone (section between substations) and to define the interference on code current flowing in rail lines. Thus, it is necessary to carry out a mathematic model of the traction supply net. Also some scientific work was addressed to determine the traction current spectrum composition and the most dangerous harmonics for TC operations. This paper introduce a mathematical model of the railway network, which can be helpful in analysis of the impact of these faults on the railway network. It was considered as 8-poles for the one-track railway traction. As mentioned before, one of the main steps to investigate the electromagnetic interferences' impact on automatic devices of the railway system is the accurate model of traction network. The proposed model can be used when the electric locomotive current divides into two different current which flow in traction lines. Moreover, a system of differential equation regarding the proposed model was written and a solution to this system was introduced. All rail currents and the return current can be calculated from the above solution. Therefore, the impact of electromagnetic interferences on these current can be investigated.Show more Item Mathematic Model of Traction Net for the Investigation of Propagation of Harmonics in Rail Lines(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2011) Serdyuk, Tatyana N.; Gavrilyuk, Vladimir I.Show more EN: A mathematic model of traction net for the investigation of propagation of harmonics in rail lines.Show more Item The Method for Detecting Defects in Movable Armature of the Signalling Relay(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2017) Havryliuk, Volodymyr I.Show more EN: Despite significant progress in the development of microelectronic rail automatic systems observed in recent decades, relay-contact devices are still widely used in railway signalling systems, that are fundamental to the safe operation of railways and must perform predictably and reliably. Thus, signalling relays used for safety-critical or safety-related applications in railway signalling systems should be properly maintained and tested to ensure their performing safely and reliably throughout their expected service life. With the purpose of developing a method for detecting defects in movable armature of the signalling relay, the time dependences of transient currents during relays switching have been investigated for relay in various technical conditions: in operable condition, as well as with arti-ficially created defects (bends) of contact springs. The measured data have been analyzed in the time and frequency domain using the wavelet transform modifications (CWT, DWT, DWPT). The analysis of the transient currents was carried out using segmentation of the current characteristics of the relay. The relay transient current at first and third segments which corresponded to unmovable anchor state, increase with time during relay switchon approximately as the exponential function. The time constants of the relay current were calculated by approximating the measured currenttime dependences at the first segment of the current curve by exponential function. The presence of defects in the movable armature of the relay had practically no effect on the values of calculated time constants. However, these values strongly depended on the technical condition of the relay magnetic circuit and the relay coil, as well as on the voltage applied to the coil terminals. This behavior of the relay time constant on the first segment of the relay current characteristic makes it possible to use this parameter to monitor the technical state of the electromagnetic relay system. Defects of the armature and contact springs led to the appearance of additional features at the second segment of the relay transient current, which corresponded to the movement of the armature. The magnitude of these features on the current curve depended on the value of bending of the relay's contact spring. The width and appearance time of the features at the second segment of the current-switching curve correspond to the non-simultaneous switching of the relay contacts. To determine the amplitude (energy) of these features (peaks) on transient current curve, their duration and the times of appearance, the wavelet transform was used. The results of investigations confirmed the possibility of determining the defects of the relay movable armature by using wavelet analysis of the second segment of the relay transient current characteristic.Show more Item Modeling of Electromechanical Systems(Дніпровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2018) Buriak, Serhii Yu.; Havriliuk, Volodymyr I.; Hololobova, Oksana O.Show more EN: Real time systems mode and transmit data on the instantaneous state of the control objects can timely detect any faults and thus provide additional time for their correction by railway employees. Turnouts are one of the most important and responsible components, and therefore require the development and implementation of such diagnostics system. Achieving the goal of monitoring and control of railway automation objects in real time is possible only with the use of an automated process of the objects state diagnosing. For this we need to know the diagnostic features of a control object, which determine its state at any given time. The most rational way of remote diagnostics is the shape and current spectrum analysis that flows in the power circuits of railway automatics. Turnouts include electric motors, which are powered by electric circuits, and the shape of the current curve depends on both the condition of the electric motor, and the conditions of the turnout maintenance. For the research and analysis of AC electric point motor it was developed its mathematical model which satisfies the conditions of adequacy. The calculation of parameters and interdependencies between the main factors affecting the operation of the asynchronous machine was conducted. The results of the model operation in the form of time dependences of the waveform curves of current on the load on engine shaft were obtained. On the basis of the constructed model we can study the AC motor in various mode of operation, record and analyze current curve, as a response to various changes of the load on engine shaft.Show more Item Modeling of Rectangular Pulse Oscillator of Electrical Tonal Rail Circuit(Dnipropetrovsk National University of Railway Transport Named After Academician V. Lazaryan, Dnipropetrovsk, 2016) Romantsev, Ivan O.; Taynolyub, Mykola S.Show more EN: circuit it is necessary to determine the rectangular-pulse oscillator circuit based on integrated circuits, perform the analysis, mathematical and physical modelling, to define the parameters of each output signal. Findings. The obtained data allow to form a stationary circuit of rectangular signals oscillator of electrical tonal rail circuit excluding the output frequency and power tuning. Originality. During the work performed the simulation of amplitude-manipulated signal oscillator of electrical tonal rail circuit based on logic elements. Practical value. The data obtained allow to optimize the costs of production of tonal rail circuits equipment.Show more Item Modeling of the Traction Current Harmonics Distribution in Rails(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2017) Havryliuk, Volodymyr I.Show more EN: Electrified railways are one of the most powerful wide frequency range sources of disturbances that interference on signaling and radio communication systems. This is especially true for new types of vehicles equipped with electronic static converters with pulse width modulation (PWM), from which high-frequency interferences in rails can have frequencies up to several tens of kHz. To ensure the electromagnetic compatibility (EMC) of new types of rolling stock with signaling and radio communication systems, they are subjected to an acceptance procedure that includes on EMC tests in accordance with European and national regulatory standards and norms. But under some unfavorable operation conditions for the trains that were successfully tested and are in operation with old vehicles on the same lines (sometimes with old feeding system), the disturbing current generated by vehicles may reach values greater than the allowed values. As such unfavorable operational conditions may be considered increasing number of trains, low distance between track circuit receiver and vehicles or supply substation, low rail-to-earth conductivity and conductivity of earth. To proof the electromagnetic compatibility (EMC) between rolling stock and signalling systems it is need accurate modeling of the test cases with taking into account particular operation conditions. The aim of the work is to establish mathematical and computer model for distribution of traction current harmonics in direct feeding traction network with multiple vehicles in feeder zone. This model is an evolution and simplification of models represented earlier. The work has been performed in order to proof the electromagnetic compatibility of new trains equipped with electronic static converters with existing traction lines and has been used during tests of new types of train. The model has been simplified as follows. The lines with equal or close to each other potentials are represented as a single line with equivalent electrical parameters. The disturbing vehicles are modeled as sinusoidal current sources with several set of frequencies that are represented by currents vector. Only return current harmonics with frequencies that lie in frequency range of track circuit receiver were considered. Depended of simulation aim the values of harmonics are taken as values measured during train tests or as the maximum interference values according to norms. The distribution of the traction return current harmonics was computed for AC direct feeding traction network 1x25 kV with two-side ESS and with 1 to 5 vehicles in feeder zone. The maxi-mum interference from trains is in the areas nearest to trains and also to the point of connection of return feeder to rails (at ESS terminals). The traction harmonic current in rails are increased with increasing of train number in feeder zone and with decreasing of the rail-to-earth conductivity. The interference at 25 Hz in the rails area near the ESS for one locomotive in feeder zone don’t exceed a limit value of 1 A even in unfavorable operation conditions for of the rail-to-earth conductivity equal 0.02 Sm/km. If number of trains are increased (from 1 to 5) the interference at 25 Hz also increased and it values at rail-to-earth conductivity equal 0.02 Sm/km reach to 1.073 A for two locomotives and to 1.233 A for five locomotives, that exceed the limit value of the interference in rails at 25 Hz.Show more Item Numerical Modeling of Multimode Tweek-Atmospherics in the Earth-Ionosphere Waveguide(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2014) Serdyuk, Tatyana N.; Shvets, Аleksandr V.Show more EN: Actuality of the work. Information about the coordinates of lightning received in real time is important to assess the risk for different types of transport, power transmission and communication lines, gas and oil pipelines, protection of forests, open cast mining, industrial and port facilities. Accumulated for a long time data on the frequency of occurrence of lightning within the territory covered by the network can serve for geophysical and meteorological research, and for the purposes of ensuring safety in the design of industrial facilities and transport links. The US, a number of Western European countries, Japan, China and South Korea have national lightning detection networks ensuring the accuracy of the location of a few kilometers. This information is provided on a commercial basis. The lightning location network is based on numerous items of registration of electromagnetic radiation, equipped with fairly complicated synchronously operating equipment, and its implementation is technically difficult and expensive procedure. Alternative to the networks for many applications are single station locating systems based on the definition of the azimuth and distance to a source. However, they have much smaller precision of location determination than multi-position systems. Therefore, an actual task is to develop single-position location techniques that can increase the accuracy of determining the coordinates of lightning. The purpose of this paper is to analyze the accuracy of existing methods based on numerical modeling and development a new and improved method of single-site lightning location using ltweek-atmospherics - electromagnetic signals that represent the response of the natural Earth-ionosphere waveguide in the frequency range from 1 to 20 kHz to excitation by lightning discharges. As a result of this work methods of determining the distance to lightning are analyzed and a new method is proposed consisting in compensation of the waveguide dispersion in the signals, thus improving the accuracy of the estimates of distance to lightning in the range 100..3000 km and some ionospheric parameters, especially in the presence of noise.Show more Item An Overview of the Etcs Braking CurvesShow more EN: The purpose of the article is to present an overview of the ETCS braking curves according to the European specifications. Though the ETCS specifications lay down the basic principles for the braking curves and the associated information displayed to the driver, but there is still no harmonized method to compute them. In the absence of any requirement, the algorithms of the ETCS on-board suppliers lead to different braking distances for a given type of rolling stock. For cross border trains, the differences through national rules require the implementation in the ETCS on-board of several national braking curves. The main features of the braking curves have been reviewed in the article, including the following main aspects: basic principle to ensure of the train movement safety, the purpose and main types of ETCS braking curves, the input parameters for braking curve calculation, construction of the emergency brake deceleration curve, and guaranteed emergency brake deceleration. The basic principle to ensure the train movement safety is based on their separation in fixed block distance (for a conventional signalling system) or in moving block-sections (for ERTMS/ETCS level 3). To ensure these principles the ETCS onboard computer must predict the decrease of the train speed in the future, from a mathematical model of the train braking dynamics and of the track characteristics ahead. This prediction of the speed decrease versus distance is called a braking curve. The minimum interval between trains under automatic train protection system is defined by minimum movement authority that comprises odometer tolerance, driver allowance, ATP re-action times, brake application time. Braking curve predict of the train speed decrease versus distance by the ERTMS/ETCS on-board equipment, from a mathematical model of the train braking dynamics and the track characteristics ahead. ETCS supervises both the position and speed of the train to ensure they continuously remain within the allowed speed and distance limits, and if necessary it will command the intervention of the braking system to avoid any risk of the train exceeding those limits. There have been considered in the work the main ETCS braking curves and the supervision limits of the EBD braking curves, the movement authority, the end of authority, the most restrictive speed profile, the supervised location and others.Show more Item A Review of Power Quality Issues in Electrified Rails(Дніпропетровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2017) Havryliuk, Volodymyr I.Show more EN: Electrified railways are among of the largest consumers of electric energy with longitudinally distributed power supply stations and connected to lines fixed (unmovable) electrical loads (consumers) and moving loads (vehicles), which operate, in general case, in nonlinear pulse modes. Due to the electrical non-linear nature of power stations and loads, current and voltage distortions appear in railway lines that devastating impact on the entire power system and consumers. The development of high-speed railways and the use of new types of rolling stock with power electrical equipment and pulse-width modulation of the traction current lead to problems with electromagnetic compatibility (EMC) and power quality in feeding grids that can adversely influence on train movement safety. The purpose of this article is to give a brief overview of power quality issues in electrified railways and also to consider related PQ standards. The main power quality disturbances are illustrated by using fragments of the traction current and voltage time-dependences measured during tests of the rolling stocks on electromagnetic compatibility with rail circuits. The traction current and voltage were registered in vehicle power equipment circuits, using a current and voltage probes whose signals were converted by analog-to-digital converter and recorded by PC. The different definitions of power quality presented in standards and literature are discussed.The main power quality disturbances were illustrated using specially chosen characteristic fragments of registered traction current, and some their parameters and electrical processes caused them are considered.Show more Item Tomography Technique for Global Lightning Imaging from Ambient ELF Electromagnetic Noise(Дніпропетровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпропетровськ, 2011) Shvets, Аleksandr V.; Serdyuk, Tatyana N.Show more EN: The article investigates tomography technique for global lightning imaging from ambient ELF electromagnetic noise.Show more

Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна