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The partitioning of railroads electrified on dc is done with the help of insulating air gaps (IAGs). When the pantograph collector of an electric locomotive crosses the branches of an IAG, an increment in current occurs in the feeder of the traction network entered by the electric locomotive. In these cases, the nonselective operation of a high-speed circuit breaker (HSCB) results in its false response, disconnection of the traction network power supply area, and, ultimately, stops the train. To preserve the reaction of the protection to a remote short-circuit and avoid false tripping in circuit-breakers, an interlocking circuit is proposed that prevents the tripping of HSCBs of adjacent dc traction network feeders at an instantaneous increment in current.

Three-motor synchronous drive system is a multi-input multi-output, nonlinear and strongly coupled system, which is widely used in the driving field of high precision coordinated control such as paper-making, printing, electric locomotive, etc. A mathematical model of three-motor drive system is analyzed and a new control strategy is proposed for the decoupling control of speed and tension of three-motor drive system, in which the core is fuzzy first-order active disturbance rejection controller (ADRC). Various disturbances from the outside and the inner model are observed and compensated by an extended state observer. As the parameters of the active disturbance rejection controller are adjusted online by a fuzzy controller, the performance of the controller is thus effectively improved. The anti-interference performance, decoupling performance and tracking characteristics were tested based on laboratory-developed multi-motor experimental platform. The experimental results demonstrate that the proposed strategy can effectively decouple speed and tension. The system has fast dynamic response, low overshoot, high steady-state accuracy and good tracking performance.

This paper presents the results of a study of the effect of the characteristics of the traction power-supply system on the indicator of the energy supply of electric rolling stock. The power-supply indicator of the electric locomotive is described as a function of the indicators of the load capacity of a traction power system and operational indicators of the transportation process: the mass of trains, speed, headway, and a number of others. Statistical methods and results of the evaluation of the effectiveness of the use of traction resources for the territorial branch of the operating domain on the basis of rolling stock quality indicators have been presented. The organizational structure and model of the management of traction resources taking into account the inclusion of the functions of the relationship with the territorial directorates of Transenergo have been presented.

A dc electric locomotive simulation model is considered that makes it possible to study transient and steady processes and may serve as a basis for the notion of a “digital locomotive” being implemented within the “Digital Railway” project. One of the most popular electric locomotives is selected, which is designed for pulling freight trains along long-distance railways electrified with direct current with a voltage of 3000 V. The electric locomotive model is based on a mathematical model of a collector traction engine. The model takes into account the nonlinearity of the main pole’s magnetic characteristic, as well as the effect of eddy currents in solid magnetic circuit sections on the magnetic flux variation. The model provides a mechanism for regulating motors in the course of investigations in accordance with operating conditions. The processes of resistor starting and voltage regulation by connection to resistors by means of transposition, as well as motor regulation by changing the magnetic flux, are taken into account. The possibility of using the developed model to study the traction substation–traction network–electric rolling stock system, which is determined by different operating modes of the traction network in the process of converting electrical energy into mechanical, is shown. Calculations of various locomotive operating modes in the event of failure in the contact network are carried out.

A mathematical model of the “traction network–ac electric locomotive with four-quadrant converter” electrical system is proposed. Analysis of electromagnetic processes is carried out. Calculation formulas of the system parameters are derived, and the results are presented in graphs. A mathematical model of the electrical system is proposed. Software implementation of the proposed mathematical model and numerical studies of reproducible electromagnetic processes are carried out in the Simulink package of the MATLAB computing environment. Conclusions about the electromagnetic compatibility of electric locomotives with different traction converter structures are drawn.

The calculated power characteristics of the traction drive of the 2ES5K electric locomotive have been considered in the middle of a feeder zone of the overhead contact system. The traction drive with the developed converter of input electric resistance demonstrates advantages over the entire range of control, especially in the initial low-power region. The voltage waveform distortion factor for a current collector of the locomotive with a reversible converter is about 10.87%; if an electric semiconductor variator is used, this factor is 7.5% in the same mode of engine handling. It has been shown that control over the power of a locomotive by means of changing the electric resistance during the transfer and consumption of electricity from the overhead contact system leads to an increase in the energy efficiency and electromagnetic compatibility with power-supply systems without using additional equipment.

Dependences between the currents and voltages at terminals of a homogeneous long line were analyzed. They make it possible to more correctly explain the changes in current and voltage in an electric-traction network when switching the thyristor arms of a rectifier–inverter converter than do conclusions obtained during replacement of a long line with a circuit with lumped parameters. An imitation model of the homogeneous low-loss long line in the MATLAB/Simulink software environment is proposed that adequately represents the propagation of incident and reflected electromagnetic waves along the line. Transfer functions are presented that approximate the frequency dependences of the specific parameters of the equivalent rail–ground loop and the overhead catenary–ground loop calculated taking into account the increase in the resistance of the wires due to the eddy currents and the surface effect. The influence of frequency dependences of the specific electric parameters of an electric-traction network calculated by various methods on the free voltage oscillation decay on the electric locomotive pantograph obtained by modeling the electromagnetic processes in the traction substation–electric traction network–electric locomotive system is revealed.

An assessment of the overall performance of 3ES5K alternating-current electric locomotives with a collector drive in the regimes of traction and recuperative braking using the concrete example of a staged route between the Khabarovsk-2 and Bikin stations of the Far East Railroad is given in this article. Real traction and brake characteristics of a 3ES5H electric locomotive in the case of a cargo train of large weight and length are shown. Analysis is carried out of all the characteristics of a 3ES5H electric locomotive, and they are compared with the movement of a 2ES5 electric locomotive with an asynchronous drive. It is determined why 3ES5K electric locomotives are more power efficient than 2ES5 ones.

—“The Technical Maintenance Regulations of Russian Federation Railways” and “The Arrangement Regulations of the Russian Federation Railways Traction Power Supply System (TsE-462)” set out clear requirements to ensure minimum voltage in the aerial contact wire for freight and high-speed passenger train movement. These requirements are confirmed by the Norms of the European Electrotechnical Standard EN 50163 (1995). However, the voltage norms at traction substations (TsE-462) are in contradiction to the maximum continuous voltage in the aerial contact wire demanded by Railway Research Institute (VNIIZhT) and accepted by EN 50163 Standard. This paper proposes using continuous voltage at traction substations in the normal operating mode in the range of from 3600 (the minimum value) to 3700 V. The maximum voltage (3700 V) was obtained as a result of electrical calculation of the traction power supply system at the track sections with hard mountainous track profile while running trains with an increased weight of 6300–9000 t or two combined trains with a combined weight of 12000 t with powerful electric locomotives of 2ES6, 2ES10, and 3ES10 series. This voltage value was confirmed by long-term operation on a Tyumen–Yekaterinburg–Perm–Balezino track section of 923-km length with voltage stabilization at the level of 3650 V at the traction substations. The voltage levels at the traction substation buses are provided by a contactless automatic control system (CACS) with ±0.6% inaccuracy. The maximum voltage in the traction substation buses is acceptable and equal to maximum aerial contact wire voltage (4000 V) under the recuperation mode.

A device for improving the power factor for ac electric locomotives that are based on an adjustable passive reactive-power compensator is described. This compensator configuration allows an increase in the power factor of an electric locomotive in all its operating modes. The control of the compensator unit is based on the method of extremal voltage control at the output of an autonomous voltage inverter (AVI). The voltage is chosen on the basis of the numerical differentiation of the dependence of the power factor on the AVI voltage. The mathematical simulation of the operation of the compensator with an extremal regulator, which was performed in the MATLAB package, showed that the proposed device is highly efficient.

In an electric locomotive, the failure of any element or unit of the control system does not have to cause damage to power circuits or emergency operation. A control strategy for a four-zone ac–dc power converter with a discharge diode branch, which is connected in parallel to the rectified current circuit, is proposed. Such control improves the switching conditions of thyristors and allows reduction in the switching time and a decrease in the equivalent inductive reactance of the ac circuit; in addition, it provides reservation due to simultaneous switching of paralleled thyristor branches and skipping of control pulses in any control zone.

Failures of reversible converters (RCs) in ac electric locomotives can cause failures of ac locomotive power equipment. Depending on their severity, the electric locomotive can be placed in one of several different modes, from partial loss of function to complete halting. With this in mind, it becomes important to develop (upgrade) diagnostic support of RCs and decide on a procedure of diagnostics that would make it possible to identify defects of RCs not only in the running mode, but also in the stationary mode, during scheduled and unscheduled repairs of an electric locomotive. To provide a more reliable evaluation of the technical condition of the RC functional control, is necessary to check the connections between the converter parts. It is also important that the diagnostics allows modifications of input signals supplied to the converter inlet, depending on the results of a scheduled check for specifying the diagnosis and troubleshooting. The stationary automated diagnostics system makes it possible to determine the technical condition of an RC in the rectifier mode in stationary conditions and is intended for use in testing an RC exposed to simulated operational effects. In the current phase of development, the diagnostics system allows evaluation of the capacity and correctness of implementing the RC control algorithm in all four adjustment zones, as well as identification of RC leg interruptions. Together with the algorithm for RC diagnostics, the suggested method makes it possible to conduct functional tests and identify a particular defect, as well as check the operation of the RC by monitoring the work of the converter as a single diagnosed object before the RC is installed on the locomotive. This will ensure faster and more reliable diagnostics and make it possible to almost completely avoid the use of RCs with unidentified defects.

A method for improving the power factor of an ac locomotive with the commutator motor operating in the regenerative braking mode is proposed. The method improves the control system algorithm of the power converter. The new switching method of inverter thyristors regulates the curve of the instantaneous power during the main switching. It allows reducing the period in which the energy flow passes to the locomotive, leading an increase in the average value of the instantaneous power. A “traction substation–electric traction network–locomotive in the regenerative braking mode” mathematical model is presented to verify efficiency of the method. The model consists of several interacting electric power substations, a section of electric traction grid, a locomotive power transformer, a four-zone inverter, a control system of reversible converter, and a dc circuit. The model is realized in the OrCAD software.

Comparative analysis of conditions of interaction of locomotive wheels with rails is provided under electric and diesel traction for an open-pit railway transport. A description of conditions that promote the formation of welding bridges (setting) between microbridges of the contacting surfaces is given. Conclusions are drawn on the influence of the interaction modes of locomotive wheels with the rails on their traction ability.

Testing electric machines during production and after overhauling is one of the basic production stages, which has a direct effect on the quality of the final products. Increasing the level of automation of the testing process to the point of total elimination of the human factor has been an unsolved problem until recently. On commission from ZAO Transmashkholding and OOO Novocherkassk Electric Locomotive Plant (NEVZ) and jointly with the latter, that task was accomplished for the entire range of the traction and auxiliary motors produced by this plant. The specifics of the methods for testing dc and ac electrical machines in accordance with the regulations of the normative documentation—in particular, those that concern the loading conditions—brings about difficulties in the creation of power static converters and automation equipment for test benches to test dc and ac electrical machines. The modes of loading the machines in accordance with a back-to-back diagram required tailored power transformers and converters. The creation of automatic control systems for power equipment—in particular, automated means for measuring the electric and the mechanic parameters of the testing process—necessitated development of complex systems that operate on the “conveyor belt” principle. All safety requirements were met, easy operation was ensured for personnel, the risk of committing errors was minimized, and an acceptable rate of the testing cycle was guaranteed. Operation of the electrical machine test facility at OOO NEVZ over a number of years has proven the effectiveness of the solutions that have been developed. This article describes the experience of developing and producing electrical equipment and automatic control systems for automated test benches to test electrical machines, methods for solving problems that arise when designing such equipment, and examples of different approaches to the design depending on production specifics. Circuit diagrams of the electrical equipment for industrial tests of traction electric motors are provided.

Comparative analysis of results of modeling the motion of two 2ES5K electric locomotives on a standard railway section with a hilly profile (type III), which is regulated by the normative documents, is carried out in this paper. These electric locomotives are equipped with controllable reactive power compensating devices. As a result, we obtained consumption graphs of active, reactive, and apparent energy for the electric locomotives, as well as their recoil by the traction substations. We calculated the specific energy consumption for traction based on these data, as well as the average factors of power and reactive power. Comparison of the simulation results for electric locomotives with the standard power scheme and electric locomotives equipped with the onboard reactive power compensating devices is carried out using this data. It is shown that the use of controlled reactive power compensators leads to a significant reduction in the consumption of reactive power by the electric locomotives and losses of active energy in the traction network.

A method of improving the power factor of single-phase valve rectifiers for ac electric locomotives is considered. This paper is important because of the need to design and improve technological means of ensuring energy efficiency of electric transport and solve the important problem of conserving energy. A previously proposed circuit design of the four-zone ladderlike valve rectifier made it possible to improve the power factor by 4–5% by modifying the topology of valve gates and the algorithms of their control. The considered rectifier was further improved by changing the principle of regulation by average rectified voltage in the domain of the lowest power factor values corresponding to zone 1. The shares of reactive power and levels of higher harmonics determined by the shift and distortion factors were calculated for sectoral regulation. The efficiency of sectoral regulation as a method of improving the power factor of the four-zone ladder-type rectifier for ac electric locomotives was evaluated.

Efficient use of fuel and energy resources is a high-priority area in the energy development strategy of railway transport up to 2030 adopted by OAO Russian Railways. Currently, ac electric locomotives with power rectifier–inverter transformers make up the majority of the usable fleet, in the range of 0.65 to 0.85. This is a cause of not only significant energy losses in the network of traction energy supply, but also restrictions affecting the speed of the locomotive. The energy characteristics of ac electric locomotives can be imptoved via compensation of the reactive power component. The reactive power compensator consists of series-connected capacitor C and inductance L connected to the secondary winding of the transformer. The LC circuit parameters are calculated for reactive power compensation of an electric locomotive in the nominal operation mode. In this article, a reactive power compensation device for electric locomotive made based on a regulated passive compensator was considered. The management of reactive power compensator is carried out by means of extreme control method. It is shown that the extreme control method for a reactive power compensator does not provide for direct calculation of the reactive power of an electric locomotive and significantly simplifies the management structure of a reactive power compensator.

An analysis of the results of simulation of electromagnetic processes in the “traction substation-catenary-electric locomotive” system with electric locomotives working in the feed zone in the traction and regenerative braking modes at different distances from the traction substation is carried out. A real-time computing complex was used for simulation. The mutual influence of electric locomotives and dispensing of active and reactive power was reviewed.

The issue of determining the parameters of a promising two-system of freight electric locomotive is reviewed with consideration of the main directions of improvement of the technical parameters and characteristics of the rolling stock provided by the “Strategy of Development of Railway Transport of the Russian Federation to 2030.”

A device for the precise compensation of the reactive power of an electric locomotive is considered. The device is designed based on a passive compensator, a boosting transformer and a self-commutated voltage inverter. The simulation of various locomotive operation modes proved the high efficiency of the suggested compensator design.

Issues of modeling abnormal situations in AC traction electromechanical complexes with IGBT converters of supply voltage of traction induction motors are considered. Structures of protection systems in the form of Petri backbone networks are presented.

The grounds for variations in individual exciters of each traction drive for load balancing in a multiple-motor collector electric drive are given. A mathematical description of the relations of torques, armature currents, and excitation currents of traction motors is presented. A control algorithm for the torques of traction motors with individual excitation in a multiple-motor traction electric drive is proposed.

With an aim to optimize investment expenses and minimize power inputs for train traction, it is proposed to consider electrified sections of main-line railways as unified complex mechanical systems that convert electric energy into mechanical energy and are controlled by intellectual control systems.

The character of thermo-mechanical ageing caused by growing of internal heat resistance of powerful semi-conductor devices in transforming units has been clarified. The reasons of low reliability of electronic equipment of electric locomotive are found out. The way to increase its lifetime is suggested.

A laboratory system is developed for selecting the best casing in the wheel-rim lubricator of an electric locomotive. Casings made of high-pressure polyethylene are found to match the wear resistance of the lubricant.