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Purpose. The main objective of this study is to assess the phenomena that affect the parameters of power quality, to consider ways to counteract the deterioration of power quality, to assess the effect of electromagnetic interference on the human body, and to review the available devices for measuring the parameters of electric energy. Methodology. To obtain relevant data, the authors conducted a literature review on the topic of the work using full-text and abstract databases. The main causes of electromagnetic compatibility (EMC) violations and ways to counteract these violations are considered. The main parameters of electricity quality, conditions for their measurement and permissible ranges according to the State Standards of Ukraine (SSU) are highlighted. A review of devices for measuring the parameters of electricity quality and the search for a suitable one that meets Ukrainian standards was carried out. Findings. The authors have proved: 1) the problem of measuring electricity quality parameters is relevant and important for its accurate accounting; 2) control of electricity quality parameters and compliance with state standards allows avoiding negative impact on the electricity supply system; 3) the use of modern digital measuring devices provides greater measurement accuracy than analog ones, and they are able to take into account more parameters in one measurement. Originality. The authors conducted a study in the field of electromagnetic compatibility in the field of electromagnetic compatibility using a digital device that gives more accurate and reliable results of power quality parameters. Practical value. Based on the results obtained, it is possible both to correct the personal research of individual scientists or teams of scientists and to predict further prospects for the development of the subject area «Electromagnetic Compatibility» in traction power supply systems in railway transport. The research can also be useful in the study of the disciplines «Electromagnetic Compatibility of Railway Automation Systems» and «Electrical Circuits and Lines of Railway Automation», organization of scientific and practical seminars, advanced training courses, etc.

Purpose. Given the need to improve the performance of modern mainline rolling stock, the authors analyze the possibility of using deeper regulation of attenuation. Methodology. The analysis of the operation of the thyristor-pulse converter of ER200 electric train is performed. It is established that in the acceleration mode at the limit traction characteristic it is necessary to consider two zones: the zone of constant value of traction force and the zone of constant power. A method for determining the minimum value of the attenuation coefficient for different types of DC and PC traction motors was proposed. The methods of theoretical research and analytical calculation of electrical circuits, theoretical foundations of electric traction, mathematical modeling of electrical and energy processes were used for the analysis. Findings. The complex of theoretical research and calculations allows confirming the technical possibility of deep attenuation use to regulate the speed regulation and obtain additional across-the-line positions for the rolling stock with DC and PC traction motors. The minimum attenuation coefficient value for different types of traction motors was determined. Originality. The methodology for determining the minimum value of the attenuation coefficient for traction motors of main electric locomotives in terms of using deeper magnetic flux control, replacing the use of experimental research data with theoretical studies. The essence of the studies is to form the required type of the limit traction characteristics by reducing the minimum permissible value of the excitation coefficient, which will reduce the electricity consumption. The research on determination of quantitative indicators of electricity consumption for the analysis of energy saving reserves on the main transport was further developed. Practical value. The results of theoretical research can be the basis for the modernization of main electric locomotives of direct and pulsating current with the systems of deep attenuation regulation. The research conducted will make it possible to create recommendations on designing the systems of magnetic flux regulation for traction engines with the improved technical and economic characteristics which are capable to increase the transport process efficiency on the main transport.

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 stochastic 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 registrograms of voltages and currents were used. Findings. A computational and experimental method for estimating recuperative 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 intensity 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.

Purpose. The main purpose of the work is the development of identification models and a new method of modeling electromagnetic processes in electric traction systems with simultaneous consideration of all its subsystems, as well as several feeder zones of the electrified section. Methodology. To achieve this purpose, the methods of mathematical modelling, the basics of the theory of random processes and the methodology of their probabilistic-statistical processing, the methods for solving integral equations and analysis of electric traction circuits in electric traction systems are used. Findings. The requirements to be met by an adequate, stochastic identification model of electric traction devices are established. The solution of Fredholm’s integral correlation equation of the first kind is performed. The analytical expression of the identification dynamic model of the electric locomotive DE–1 is obtained and its adequacy is checked. The methodology of combined modeling of electromagnetic processes in devices and subsystems of electric traction systems is developed and presented tabularly. Originality. For the first time it is proposed to use the pulse transition function as identification models of traction substation and traction network with electric rolling stock in predictive modeling of electromagnetic and electric power processes in electric traction systems. A new method has been developed, a method of complex modeling of electromagnetic and electric power processes in the system of electric traction with simultaneous consideration of all its subsystems, as well as several inter-substation zones of the electrified section. For the first time, a method of partitioning the correlation functions for solving an integral correlation equation has been proposed, which allows defining a pulse transition function as an identification model of any subsystem of an electric traction system. Practical value. The developed identification models and the method of combined modeling make it possible to predict electromagnetic processes simultaneously in all feeder zones of the electrified section of the electric traction system. The obtained identification model of the electric locomotive DE–1 can be adapted with its subsequent use in modeling processes in the traction circuits of electric locomotives of other types. The method of factorization of correlation functions used in solving the Volterra integral correlation equation of the first kind (convolution type) can be adapted to the solution of other integral equations, which describe the processes in electric traction systems.

Purpose. The scientific work provides for the development and justification of a new method for the parametric identification of electric traction devices based on a system of orthogonal functions, namely – on the basis of time power series. Methodology. To solve this problem, we use: the theory of power series; basic laws of theoretical electrical engineering, elements of the spectral analysis of periodic and non-periodic non-sinusoidal functions of electrical quantities of voltage and current; matrix methods for solving a system of algebraic equations. Findings. A new method of time power series is developed, which can be used to identify devices both traction power systems and electric rolling stock. The method is based on the compilation of integro-differential equations of the electromagnetic state of the electrotechnical system under study. The given voltage and current in the indicated equations are approximated by power series, into which the required parameters of the electric circuit of the system enter in the form of coefficients. Using the developed method, electric locomotives AC of DSС3 and 2ES5K were identified in the work. Their parameters R and L, varying in time over the period of the applied sinusoidal voltage, are determined. Time dependences R(t) and L(t) are constructed and analyzed. An explanation is given for the regions with negative inductance. It is shown that these electric locomotives can be identified by a passive two-terminal network with parametric resistive and inductive elements. Originality. Innovation of work consists, first, in development of a new method of identification, and secondly, in the possibility of replacing any device of electric traction with parameters of RL- a two-terminal network. And, finally, the fact that the proposed method makes it possible, by improving the approximation of input and output voltages and currents, to obtain the most accurate values of the parameters R and L the identification two-terminal network. Practical value. The developed method makes it possible to evaluate the parameters of devices of electric traction systems on a real-time scale, which facilitates its application in modeling the transient electromagnetic processes that arise during the operation of the system under study in emergency modes.

Purpose.The scientific work is intended to analyse the expansion of the load range and the implementation of regeneration braking (RB) of the direct current drive by using the supercondenser power storage units. Methodology.To solve the problem, we use the methods of the electric drive theory, impulse electronics and the method of calculation of transient electromagnetic processes in linear electric circuits in the presence of super-condensers therein. Findings.The stiffness of the mechanical and electromechanical characteristics of a series motor is significantly increased, which makes it possible to use a DC drive under load, much smaller than 15…20% of the nominal one. Numerical calculations of the operation process of the supercondenser power storage unit were fulfilled with a sharp decrease in the load of a traction electric motor of a direct current electric locomotive. The possibility of RB of the direct current drive with the series motor is substantiated. The equations of the process of charging and discharging of super-condenser storage unit in RB mode are solved. The authors examined the effect of capacitance on the nature of maintaining the excitation current of an electric motor in the mode of small loads.Originality.The paper developed theoretical approaches for the transformation of soft (mechanical and electromechanical) characteristics into hard ones of DC series motors. For the first time a new, combined method of the series motor RB is proposed and substantiated. Further development obtained the methods for evaluating the storage unit parameters, taking into account the criteria for reliable parallel operation of super-condensers with an electric motor field. Practical value.The proposed and substantiated transformation of soft characteristics into stiff ones allows us to use general-purpose electric drives with series motors and at low loads, and in traction electric drives - to reduce the intensity of electric stockwheel slipping. Thedevelopedmethodofsolvingtransitionalequationsmakesitpossibletotakeintoaccounttherandomnatureofthevoltagechangeonthemotorinsuper-condenserdrivechargeanddischargemodes. The proposed combined method makes it possible to carry out RB at low speeds of the motor armature as well, and thus to increase energy efficiency of operation of electric drives of this type.

Purpose. Development and substantiation of a new method of structural identification of electrical devices of electric traction systems for both DC and AC current. Methodology. To solve this problem the following methods are used: the methods and techniques of the linear electrical engineering, in particular, the Laplace operator method; the numerical method for solving the integral equation, which is based on the representation of the Wiener-Hopf linear equations system (this allows forming the solutions of the problem in a mathematical form of the correlation and weight functions); the factorization method, which provides certain partition of the correlation functions of the stochastic processes. Findings. It was developed the method of weight function of the electrical devices identification, which can be fully used in the systems of electric traction. As the use example of the developed method it was considered a feeder section of DC electric traction with the single power supply. On this section move two electric locomotives of the type DE 1, they have been identified by the weighting functions. The required currents and voltages of electric locomotives are also formulated in the electric traction network in probabilistic and statistical form, that is, the functions of mathematical expectation and the correlation functions are determined. At this, it is taken into account that the correlation function of the sum of random functions is equal to the sum of the correlation functions of additives, and the correlation function of the integral of a random function is defined as the double integral of the correlation function of the output of a random function. Originality. Firstly, originality consists of the adaption of the developed method of structural identification for the devices of electric traction system. Secondly, it lies in the proper development of the new method of weight function. And finally, it lies in the solution of the Wiener- Hopf equation using the correlation method of factorization. Practical value. The developed method and the technique that is based on it, allow predicting electric traction loadings of the traction network, as well as the other devices of the traction energy systems and the electric motive power in the different modes of operation and, in particular, during the high-speed train traffic. The method takes into account the load influence (and its mode of operation) of the adjacent feeder zones on the electromagnetic processes in the studied inter-substation area. Thus, it is important that the required voltages and currents are considered as the random functions.

Purpose. Defining and analysis of the probabilistic and spectral characteristics of random current in regenerative braking mode of DC electric rolling stock are observed in this paper. Methodology. The elements and methods of the probability theory (particularly the theory of stationary and non-stationary processes) and methods of the sampling theory are used for processing of the regenerated current data arrays by PC. Findings. The regenerated current records are obtained from the locomotives and trains in Ukraine railways and trams in Poland. It was established that the current has uninterrupted and the jumping variations in time (especially in trams). For the random current in the regenerative braking mode the functions of mathematical expectation, dispersion and standard deviation are calculated. Histograms, probabilistic characteristics and correlation functions are calculated and plotted down for this current too. It was established that the current of the regenerative braking mode can be considered like the stationary and non-ergodic process. The spectral analysis of these records and “tail part” of the correlation function found weak periodical (or low-frequency) components which are known like an interharmonic. Originality. Firstly, the theory of non-stationary random processes was adapted for the analysis of the recuperated current which has uninterrupted and the jumping variations in time. Secondly, the presence of interharmonics in the stochastic process of regenerated current was defined for the first time. And finally, the patterns of temporal changes of the correlation current function are defined too. This allows to reasonably apply the correlation functions method in the identification of the electric traction system devices. Practical value. The results of probabilistic and statistic analysis of the recuperated current allow to estimate the quality of recovered energy and energy quality indices of electric rolling stock in the regenerative braking mode. But the correlation and spectral analysis is required to determine the electromagnetic compatibility of the electric rolling stock in the regenerative braking mode with the subsystems and the electric traction devices.

Purpose. Development and theoretical ground of the analytical method for the calculation of the active, reactive and total powers in the electric traction devices, taking into consideration the non-stationary character of the stochastic processes change of the voltage and current in the elements of these systems. Methodology. The mathematical methods of the random processes theory and the “discrete electrical engineering” methods are used for solving the main problem of this paper. Findings. The Method of the Correlation and Dispersion is developed for definition of the active power, the reactive power by Fryse and the total power of the devices in the elements of the electric traction system of the main-line railways. The method is based on the well-known concepts of auto- and inter-correlation functions of the random processes which govern the feeder voltages and the currents in the traction power supply subsystem as well as the currents and voltages of the electric rolling stock. The method developed in this paper allows estimating the powers of both stationary and non-stationary processes. This method can be used for the analysis of both the traction mode and the regenerative braking mode of the electric rolling stock. The total power components were calculated for the one of the feeder areas of the Prydniprovsk railway using this method. The results show the significant flow of the reactive power in the traction power supply system. This fact is also confirmed by the high values of the reactive power coefficient. Originality. Scientific novelty of the research is consisted in the following. Firstly, for defining the active and reactive powers in elements of the traction power supply system the new method (the Method of Correlation and Dispersion) is created and grounded. This method is different from other existing methods because it takes into consideration the varying non-stationary character of the chance processes of the feeder and substation voltages and currents. Secondly, in the DC traction power supply system the large values of the exchange reactive power by Fryze were created for the first time. Practical value.The method and its technique allow calculating the main energy coefficients for the traction power systems such are the reactive power coefficient, the main and additional active power losses in the power circuit of the electric rolling stockand the traction power supply system.

Analytical expression has been evaluated and instantaneous reactive power as a sign of exchange electrical energetic processes in the system of electric traction of direct current have been calculated.

Describes the method for calculating in complicated closed electrical networks. Mathematical description of the system is based on the use of graphs and matrices.

The method of automated diagnostics of electric motors is offered. It uses a neural network revealing the electric motor faults on the basis of analysis of frequency spectrum of current flowing through the motor.

The efficiency of compensation of capacitor currents of single-phase short circuit on ground corresponds to a resonant, or close to it, mode of adjustment of the compensating device. In the paper the critical analysis of the most widespread methods of automatic adjustment of arc extinguishing reactors and the opportunity of their use in dynamical distributive networks is given.

In the article the influence of resistance of secondary winding of the high-voltage measuring current transformer on the error of device of its compensation is considered.

The combined system of active filtration of target voltage of the rectifier using an added voltage converter as an in-series link and a high-frequency current inverter as parallel one is offered. Its application allows reducing weight of a choke of the passive filter.

The microprocessor device of protection of electric chains of electric motors from short circuit currents, in which switching-off of a short circuit current is carried out before it achieves a shock value, is presented.