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Purpose. The study is aimed at substantiating the structure and determining the main parameters of the traction electric drive of an electric locomotive for railway quarry transport, taking into account its modes of operation. Methodology. The research was carried out by means of mathematical modeling, which included solving the traction problem and evaluating the parameters of the energy exchange processes between the components of the traction electric drive. The simulation was carried out for the movement of the train along the track section and during shunting, which differ significantly in their mathematical description. During simulation of movement along the track section, the traction problem was solved using recommendations for traction calculations for train operation. A simplified model was developed to simulate movements during shunting. Determination of the parameters of the traction electric drive components is carried out by analyzing the processes of energy exchange in the traction electric drive based on the power balance. During the studies, it was assumed that the on-board energy storage in the traction mode feeds the traction electric motors of the booster section. In the electrodynamic braking mode, the energy accumulator stores energy from all traction electric motors of the electric locomotive. Findings. The authors obtained time dependences of the parameters that characterize the train movement at all stages of the cycle «empty half passage – loading – loaded half passage – unloading» (on the example of an electric locomotive for PJSC «Ferrexpo Poltava Mining»). The analysis of the obtained dependencies made it possible to determine the parameters of the main components of the traction electric drive for the proposed storage operation scenario. It was established that the energy capacity of the energy storage should be 250 kWh for one movement cycle. The energy storage power is 6000 kW. Originality. The authors of this paper for the first time proposed the structure of the traction electric drive of an electric locomotive for quarry railway transport, in which the electric motors of the control electric locomotive are powered from the catenary network, and the electric motors of the booster section are powered from the energy accumulator and are included in the operation at a load that exceeds 50% of the nominal one. Practical value. The practical value lies in the developed mathematical models of movement and energy exchange processes, which can be applied to the study of traction electric drives of vehicles of various purposes.

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. 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. When locomotives move in curved sections of the railway track, horizontal forces arise, which lead to pressing the ridge of the wheel pair to the railway track. The article is aimed to develop a method for determining the frame force acting on the bogie from the side of body of the locomotive section using the current methodology of calculating the lateral force. It is also aimed to determine the basic parameters that influence the value of the frame force. It is necessary to construct the dependencies of the frame force on the travel time of electric locomotive in the corresponding curve changing these parameters. Methodology. As is known, the electric locomotive is a multimass mechanical system. We will assume that this system consists of seven bodies: a body, two frames of carriages and four wheel sets. To determine the lateral force acting on the rail from the wheelset one need to solve differential equations of motion of locomotive bogie in curves of small radius. Using the equations of kinetostatics for wheelset one should come to determining the frame force acting on the car bogie from the side of body of the locomotive section. The nominal geometric and mass parameters of parts and components of electric locomotive are taken in the calculations. The curve radius, the length of transition curve, the length of circular curve, the longitudinal slope of railway track and other parameters are fixed values. Findings. There were obtained calculated values of the frame force of electric locomotive VL80 acting on the bogie from the side of body of the locomotive section. Based on the obtained results there were built the dependencies of frame force on the travel time of electric locomotive on the corresponding curve when changing the speed and corresponding elevation of the outer rail. Originality. On the basis of the existing methodology for calculating the lateral force it was developed the method for determining the frame force acting on the car bogie from the side of body of the locomotive section. Practical value. Improving the method for determining the frame force improves the accuracy of calculations when analyzing the traffic safety and when conducting the forensic rail-transport examinations.

Purpose.The railways of Ukraine have been operated the locomotives, which are both morally and physically obsolete. Therefore, to ensure the competitiveness of rail transport it is necessary to update the locomotive fleet, and first of all the fleet of electric locomotives, because electrified railways provide the greater part of passenger and freight traffic. In this connection it is of special importance to determine the optimum parameters of the nominal mode of electric rolling stock. The purpose of the work is to examine the features of solution of these problems with respect to electric locomotives. Methodology. Assuming that the limit values of traction force are determined by the conditions of wheel-rail grip, then the power of the nominal mode can be represented as the product of rated speed, estimated friction coefficient, train weight and the coefficients that represent the ratio of the estimated (starting) value of traction force to value of traction force the nominal mode and the ratio of the mass of the locomotive to the train weight. Since the mass of the train is not a constant value, there is always a surplus power of the locomotive fleet required for the mastering of a predetermined volume of transportations. Reduced overcapacity of the locomotive fleet can be achieved by introduction of the locomotives of different power, designed for driving trains of different weight that will result in increased completeness of the power use but also in difficulty in selecting of locomotives for trains in operation. The paper shows the method of calculating the optimum values of power, speed and traction force of the nominal mode. It presents the mathematical model of the relationship of traction rate, excessive capacity and power of the traction unit. Findings.It is proved that the power of the traction unit, the total fleet power requirement and the excess of power in absolute units are proportional to the speed of the nominal mode. To reduce the total power of the fleet when selecting the optimum power of the traction unit it is necessary to take into consideration the speed of the nominal mode, defined by the condition of minimization of power consumption for traction, i.e. the smallest value that enables the implementation of the given running speed and the powerredundancy level required for operation. Originality. It consists in the development of a unified algorithm for determining the optimal parameter values of the nominal mode of passenger, freight and freight-passenger electric locomotives. Practical value. The authors determined the minimization costs during production, acquisition and maintenance of electric locomotives, whose nominal mode parameters are designed according to the above procedure.

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. The essence and basic characteristics of calculation methods of transient electromagnetic processes in the elements and devices of non–linear dynamic electric traction systems taking into account the stochastic changes of voltages and currents in traction networks of power supply subsystem and power circuits of electric rolling stock are developed. Methodology. Classical methods and the methods of non–linear electric engineering, as well as probability theory method, especially the methods of stationary ergodic and non–stationary stochastic processes application are used in the research. Findings. Using the above-mentioned methods an equivalent circuit and the system of nonlinear integra–differential equations for electromagnetic condition of the double–track inter-substation zone of alternating current electric traction system are drawn up. Calculations allow obtaining electric traction current distribution in the areas of feeder zones. Originality. First of all the paper is interesting and important from scientific point of view due to the methods, which allow taking into account probabilistic character of change for traction voltages and electric traction system currents. On the second hand the researches develop the most efficient methods of nonlinear circuits’ analysis. Practical value. The practical value of the research is presented in application of the methods to the analysis of electromagnetic and electric energy processes in the traction power supply system in the case of high-speed train traffic.

Purpose. To define the characteristics of numerical calculations of mathematical model with one or more cyclic current voltage characteristics (CVC). This is an urgent problem, since any electric traction system device and electrified track in general, like non-linear passive or active two-terminal network in the present operating mode is described by current-voltage characteristic (CVC), which is based on the given input voltage and input current. Me-thodology. The electromagnetic process calculation in the power circuits of traction electric energy supply is the probabilistic task with solving nonlinear stochastic differential equations requiring for the development of special methods. Given the calculation difficulty, it is reasonable to perform them either by real CVC graph bypass or initially by applying its equivalent replacement with, for example, an ellipse. Findings. Numerical calculations of the mathematical model with one or more cyclic CVC can be performed by “real” CVC bypass or by "idealization" i. e. approximate replacement of real cyclic CVC. Originality. This paper presents the dynamic CVC of the DS3 and 2ES5K electric locomotives at different currents of electric locomotives. Practical value. Cyclic CVC normally and definitely can be applied in the system of electromagnetic state equations while transient state calculating in the traction system. Therefore while calculating the experimentally obtained CVC for the most “difficult and complex” (or/and the “easiest”) mode is applied.

The article describes the model of vibrations of an electric locomotive ChS4. A vehicle is considered as a mechanical system of 9 rigid bodies (a body, 2 bogie frames, 6 wheelsets).

In the paper the outcomes of operations performed on the proving track section of Lviv Railways aimed at estimating the possibility of exclusion of pneumatic braking on the section Lavchne–Beskyt–Volovets as well as the possibility of exclusion of an engineering stop at the platform Skotarske from the train schedule are observed.

The article is a continuation of analysis of the electric equivalent AC circuit «traction substation − device of transversal compensation − electric-traction network − electric locomotive DS 3» and the influence on a power transformer in the idle mode, depending on the feeder voltage and the distance of an electric locomotive from a traction substation. The numeral calculations are performed and the voltage and current values in the electric power supply system are analyzed.

The article is a continuation of analysis of mathematical models for AC systems, in which the elements of electric-traction network and switch-on of power transformer in an idling mode are gradually connected. The numerical calculations and analysis of current of transformer magnetization are executed.

In the article the electric circuit of substitution and mathematical model of the system of alternating current «traction substation − traction mains − electric locomotive DS 3» at switching its power transformer on in the idle mode are presented. Numerical determinations of parameters of traction substation, rails, contact network and transformer are executed; in so doing a special attention is paid to the estimation of dispersion inductance for the primary winding of transformer.

The methods of determination of the optimal parametric series of boosters for the test desks for traction electric motors of direct current electric locomotives are offered in the article.

In the article the structural reliability of different variants of structured schemes of the steady-state converter for traction drive of promising multi-system electric locomotives with asynchronous traction engines is compared.

The results of statistical research of wear of automatic coupler body butts and thrust plates of electric locomotives are presented in the article. Due to the increased wear the mentioned elements require special attention.

In the article the structured schemes of steady-state converter are offered for traction drive of promising multisystem electric locomotives with traction engines of direct current and their comparative analysis is conducted.

This paper deals with the well-grounded proposals for improving the efficient protection of traction motors from the short circuit and the slip of wheel sets.

The methods of determination of equivalent load current in tests of electric locomotive traction engines without forced ventilation with use of the results of qualification test of engines of certain types are offered in the article.