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This study addresses the issue of carbody hunting in an electric locomotive induced by low wheel-rail contact conicity. The main objective is to mitigate this unstable motion by optimising the location of yaw dampers while ensuring bogie stability under high conicity conditions. A field test was first conducted to observe the carbody hunting behaviour, and a detailed locomotive dynamics model was then developed and validated using experimental data. The impact of yaw damper locations on locomotive stability was investigated, taking into consideration different carbody modes. The findings reveal the mechanism behind the deterioration of carbody stability due to the yaw damper installation angle and two installation layouts were proposed to enhance the carbody stability. Comparisons were then made with traditional solutions using both linear and nonlinear analysis, and experimental validation confirmed the effectiveness of the optimised yaw damper locations in improving carbody stability. This research highlights the importance of optimising the yaw damper's location to suppress carbody hunting, providing valuable insights for railway engineers and offering a promising solution for enhancing stability in high-speed train. [ABSTRACT FROM AUTHOR]

Striving to increase the speed of rail vehicles and thus improve the comfort of traveling passengers at the same time, undertakes activities in the sphere of ensuring an appropriate level of safety of rail, passenger, and freight transport. One of the elements of activities in this area is the training of train drivers. Until recently, this training consisted of a theoretical and practical part on the vehicle, alongside an experienced train driver. Considering the increasing level of automation of railway traffic control systems and locomotive equipment, as well as training costs and requirements related to the introduction of TSI, it is becoming an increasingly common requirement to conduct practical training on railway vehicle traffic simulators, while the conditions in the simulator cabin and the trainee's feelings should correspond to the actual driving conditions. A locomotive driving simulator is a system consisting of a cabin of a suitable type of locomotive or EMU, mapped in 1:1 scale, coupled with a motion excitation system and computer programs connected together forming the software of the cab visualization and dynamics system. The basic program simulating the dynamics and kinematics of the cabin's motion is a program containing a motion dynamics model that generates signals forcing the movement of the exciters on which the cabin's platform is mounted. The correct operation of the simulation model depends on the created mathematical model, which can be built in several ways. This article presents the issue of building a mathematical model describing the dynamics of the rail vehicle motion, which can then be used in the simulation model of the simulator cabin motion. Two ways of proceeding in the process of approaching the construction of a mathematical model of rail vehicle motion dynamics will be presented, with the possibility of later use in creating a simulation model of the motion of the locomotive simulator cabin. One of the possible routes was used in the past in the construction of the EP09 locomotive simulator. [ABSTRACT FROM AUTHOR]

AbstractThe intelligent monitoring of electric locomotive loading is crucial in unmanned underground systems. A CNN-based monitoring scheme with migration learning was proposed to address efficiency, abnormality, and data acquisition challenges. Locomotive loading datasets are transformed, augmented, and equalized. Our model improves performance and training by modifying the fully connected layer, using optimized learning rate decay and adaptive algorithms. Training in PyTorch, the optimized VGG19-EL migration network achieves 99.85% recognition for 2-classifications, while the optimized RESNET50-EL migration network achieves 97.3% for 10-classifications. Overall, this study proposes a reliable and efficient model for liberating workers and monitoring locomotive loading.

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The article presents the results of thermovision tests of the disc brake and the drive system components located in its vicinity on the 111Ed electric locomotive in field conditions. For this locomotive, tests were carried out on a test track to measure the temperature of the disc and the temperature of other devices that were installed close to the brake disc. These tests were performed pointwise, i.e. before and after the test, and continuously throughout the braking process. The article presents the methodology of thermal imaging research and the preparation of the camera for outdoor research with objects with different emissivity. Due to the rotating brake disc, it was decided to measure using an IR camera because measurements using thermocouples were very difficult and complex. In exceptional situations, temperature measurement using thermocouples is used, but it requires an extensive additional measurement system and signal recording, which is more expensive. Correct configuration of the IR camera to real conditions is extremely important because it directly translates into the increase in measurement error. [ABSTRACT FROM AUTHOR]

Increasing the energy performance of rolling stock is one of the most relevant railway transport. One of the ways to achieve these tasks is to determine the optimal parameters of the traction drive of the rolling stock, with which you can create computer simulation models. In this article, the optimal parameters of an asynchronous traction motor of an electric rolling stock are determined. Determination of the parameters of the ATM is necessary to create a computer simulation model that allows reproducing electromagnetic processes in a traction electric drive and converters, as well as processing functions of the simulation results obtained that are adequate to the real conditions of use on electric rolling stock of converters with various control algorithms in traction and regenerative braking modes. In the article, the modes of idling, short circuit and rated load are used to determine the parameters of the ATM in relation to the T-shaped replacement circuit using the method of separation of losses in the engine. Losses in traction converters and traction gearboxes are taken into account in accordance with the power developed by the ATM. The results obtained can be used in a computer simulation model designed to reproduce electromagnetic processes in a traction electric drive and converters, when determining the energy characteristics of electric locomotives with asynchronous traction motors.

Due to complex environmental factors such as uneven illumination and high noise, unmanned electric locomotives in coal mines have low accuracy in multi object detection and difficulty in recognizing small objects. In order to solve the above problems, a multi object detection model for underground unmanned electric locomotives in coal mines based on SD-YOLOv5s-4L is proposed. On the basis of YOLOv5s, the following improvements are made to construct the SD-YOLOv5s-4L network model. The model introduces the SIoU loss function to solve the problem of mismatch between the direction of the real box and the predicted box, so that the model can better learn the position information of the object. The model introduces decoupled heads at the head of YOLOv5s to enhance the feature fusion and positioning accuracy of the network model. It enables the model to quickly capture multi-scale features of the object. The model introduces a small object detection layer to increase the original three scale detection layer to four scale. It enhances the model's feature extraction capability and detection precision for small objects. The experiment is conducted on a multi object detection dataset of the mine electric locomotives. The results show the following points. The mean average precision (mAP) of the SD-YOLOv5s-4L network model for various types of objects is 97.9%, and the average precision (AP) for small objects is 98.9%. Compared with the YOLOv5s network model, it improves by 5.2% and 9.8%, respectively. Compared with other network models such as YOLOv7 and YOLOv8, the SD-YOLOv5s-4L network model has the best comprehensive detection performance and can provide technical support for achieving unmanned driving of the mine electric locomotives.

Purpose of the article is to demonstrate that a high-speed electric locomotive, driven by asynchronous motors in a hollow shaft arrangement and swing-out couplings, can generate corrugation conditions on the surface of new and smooth rails on straight and curved track. Most studies carried out in this area is usually concerned with the response of the power train to kinematic excitation from a track where corrugations are already present. The novelty of the look presented in the article is to establish the influence of the vehicle's driveline and the parameters of a perfectly smooth formation track on the mechanism of corrugation. A four-axle EU11 electric locomotive, produced in Poland in the late 1990s, has been selected for analysis. A complete electro-mechanical model of the locomotive was built using the Vi-Rail software and prepared for simulation on straight and curved track. A non-linear model of wheel-rail contact was included and the contact forces were determined for the locomotive model in motion with the active power system. Unbalanced inertia forces generated by the scattering of stiffness characteristics of the coupling links, have been included to the propulsion system as an additional source of dynamic excitations. The complexity of the obtained results was influenced by the fact that simulation studies were carried out in both the time and frequency domains. The results obtained in the time domain were used to calculate the vertical and torsional vibration frequencies with respect to the driving wheelsets. One of the most important results of the simulation studies carried out is the determination of the effect of locomotive acceleration on the frequency of resonant torsional vibrations of the wheelsets in straight and curved track traffic.

The problem of increasing the reliability of transport units during maintenance and repair in the locomotive depot is considered. The transient processes in the power circuit of the DC electric locomotive with traction motors was studied and a calculation scheme of a DC electric locomotive with the series connected traction motors was presented. When considering the magnetization curve linearization, small increments in the form of the system magnetization characteristic were applied. On the base of those results, it was determined that the duration of the transient process in the traction motor windings of the DC electric locomotives equals tt = 3τ. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Striving to increase the speed of rail vehicles and thus improve the comfort of traveling passengers at the same time, undertakes activities in the sphere of ensuring an appropriate level of safety of rail, passenger, and freight transport. One of the elements of activities in this area is the training of train drivers. Until recently, this training consisted of a theoretical and practical part on the vehicle, alongside an experienced train driver. Considering the increasing level of automation of railway traffic control systems and locomotive equipment, as well as training costs and requirements related to the introduction of TSI, it is becoming an increasingly common requirement to conduct practical training on railway vehicle traffic simulators, while the conditions in the simulator cabin and the trainee’s feelings should correspond to the actual driving conditions. A locomotive driving simulator is a system consisting of a cabin of a suitable type of locomotive or EMU, mapped in 1:1 scale, coupled with a motion excitation system and computer programs connected together forming the software of the cab visualization and dynamics system. The basic program simulating the dynamics and kinematics of the cabin’s motion is a program containing a motion dynamics model that generates signals forcing the movement of the exciters on which the cabin’s platform is mounted. The correct operation of the simulation model depends on the created mathematical model, which can be built in several ways. This article presents the issue of building a mathematical model describing the dynamics of the rail vehicle motion, which can then be used in the simulation model of the simulator cabin motion. Two ways of proceeding in the process of approaching the construction of a mathematical model of rail vehicle motion dynamics will be presented, with the possibility of later use in creating a simulation model of the motion of the locomotive simulator cabin. One of the possible routes was used in the past in the construction of the EP09 locomotive simulator.

There is a plethora of methods in the global literature that can be used to measure CO2 emissions from electrified transport. But are these methods reliable, and do they offer us a true view of how much exactly of this greenhouse gas is being produced by electric rail transport? We answer this question by proposing an improved CO2 emission estimation model based on cargo transport. Unlike other works, our studies include four crucial steps: (1) estimation of energy consumption in electrified rail cargo transport; (2) estimation of energy losses in the railway traction system and high voltage transmission lines; (3) CO2 emission estimation in traditional powerhouses; and (4) determination of the intensity of the CO2 emissions from electrified rail cargo transport. Based on our method, we concluded that the intensity of CO2 depends not only on the type of fossil fuel used for energy production but also on the parameters of the cargo train, such as its length and weight or the total number of wagon axles (which depend on wagon type). The achieved intensity of CO2 emissions in electrified rail cargo transport slightly varies from those reported in the global literature. Among the most important reasons responsible for this are the conditions under which these tests were conducted. Nevertheless, our results shed new light on how CO2 should be measured. We proved that the decarbonization of electrified rail cargo transport will never be possible without infrastructure modernization. In addition, based on a case study, we also delivered knowledge on how to reduce the environmental impact of electrified rail cargo transport. [ABSTRACT FROM AUTHOR]

To control a single-phase dc electric locomotive with controllable excitation converters, control principles have been formulated that make it possible to implement specified characteristics of independent or sequential excitation of traction motors. The presented control algorithm implements axis-based control of currents and traction force of an electric locomotive without disconnecting the power circuit of traction motors, which provides a constant traction force. The results of mathematical modeling of the operation of a three-unit ac electric locomotive are presented. The proposed control algorithm provides a smooth increase in the traction force of the electric locomotive to the specified values by sequential activation of traction motors. [ABSTRACT FROM AUTHOR]

Purpose of the article is to demonstrate that a high-speed electric locomotive, driven by asynchronous motors in a hollow shaft arrangement and swing-out couplings, can generate corrugation conditions on the surface of new and smooth rails on straight and curved track. Most studies carried out in this area is usually concerned with the response of the power train to kinematic excitation from a track where corrugations are already present. The novelty of the look presented in the article is to establish the influence of the vehicle's driveline and the parameters of a perfectly smooth formation track on the mechanism of corrugation. A four-axle EU11 electric locomotive, produced in Poland in the late 1990s, has been selected for analysis. A complete electro-mechanical model of the locomotive was built using the Vi-Rail software and prepared for simulation on straight and curved track. A non-linear model of wheel-rail contact was included and the contact forces were determined for the locomotive model in motion with the active power system. Unbalanced inertia forces generated by the scattering of stiffness characteristics of the coupling links, have been included to the propulsion system as an additional source of dynamic excitations. The complexity of the obtained results was influenced by the fact that simulation studies were carried out in both the time and frequency domains. The results obtained in the time domain were used to calculate the vertical and torsional vibration frequencies with respect to the driving wheelsets. One of the most important results of the simulation studies carried out is the determination of the effect of locomotive acceleration on the frequency of resonant torsional vibrations of the wheelsets in straight and curved track traffic. [ABSTRACT FROM AUTHOR]

The use of specialized rail rolling stock which is used for transporting ore from the quarry to the crushing plant at mining enterprises is analyzed here. Electric locomotives with an asynchronous traction electric drive and an on-board energy storage system are considered for use. The calculated dependencies of the electric locomotive trac-tive power were analyzed and it was established that on flat sections of the track profile, the movement is carried out with a power that does not exceed 50% of the nominal one. The movement with the nominal power is carried out on the controlled uphill during the cargo half-passage. To ensure the necessary power for movement in such areas, the use of an on-board energy storage system is proposed, which should feed the traction system while limiting the power consumed from the catenary. This happens when the voltage on the pantograph drops to a minimum level. The aim of this work is to determine the on-board energy storage system parameters during the operation of the electric locomotive with limitation of the power consumed from the traction network. Mathemati-cal models of the energy exchange processes in the electric locomotive traction system have been developed. The criteria for comparing options for calculating the parameters of the on-board energy storage system have been proposed. The criteria take into account the reduction of energy consumption during movement, the efficiency of energy storage, and the complete use of the on-board energy storage system in terms of power and working energy capacity. Based on the calculation results, it was determined that the use of an energy storage device with a power of 3,540 kW and an operating energy capacity of 63.5 kWh provides a 10% reduction in energy consumption, which is being consumed while moving along the sample section of the road. The current that can be consumed by an electric locomotive with such parameters of the on-board energy storage system is limited by 600 A.

The aim of the work is to develop a model of a hybrid reactive power compensator with adaptation of the control system to the parameters of the voltage supply. The task was achieved by applying the control algorithm for the operation of the control system of the active part of the reactive power compensator, which is based on the regression analysis method. The traction drive of the AC electric locomotive VL-80K, which is operated on the railways of the Ukraine, was chosen as the object of study. The simulation of the traction drive operation was carried out for a traction drive with and without a reactive power compensator, for cases where the process of changing the voltage in the catenary was a stationary deterministic process and for the case when this process was a non-stationary non-deterministic process. The most important result is the development of a block diagram of the control system for the active part of the reactive power compensator based on the implementation of the Levinson-Durbin linear prediction algorithm. The significance of the results obtained lies in the possibility of the proposed control scheme for the active part of the compensator to adapt the operation of the compensator to the voltage parameters of the catenary, that is, to the actual operating conditions of the electric locomotive.

The mechanical sensor of electric locomotive is easy to lose, leading to position measurement error, which deteriorates the performance of permanent magnet synchronous motor (PMSM) drive system. Therefore, a limp-home mode based on high-frequency injection sensorless strategy is proposed. The signal processing of conventional high-frequency rotating injection needs several filters, and the delay has an impact on estimated position, which is phase-based demodulation. In this paper, an amplitude-based demodulation strategy is proposed, which needs only one low-pass filter, meanwhile the digital control delay can be canceled automatically. Accordingly, the position estimation precision and robustness can be enhanced with the aid of proposed method. The feasibility and effectiveness of theoretical analysis is verified on an 18-kW PMSM drive system experimental platform. [ABSTRACT FROM AUTHOR]

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Operation modes of rolling stock at mining enterprises are considered and analyzed. The justification of the need to replace it with a modern specialized electric locomotive for quarry railway transport, equipped with an asynchronous traction electric drive and an on-board energy storage system, is presented. The determination of the parameters and structure of the on-board energy storage system, based on the condition of power compensation with limited power consumption from the traction network and ensuring the autonomous movement of the electric locomotive, is considered. This study was carried out by modeling the processes of energy exchange in the traction system of an electric locomotive. The use of lithium cells and supercapacitors in energy storage is considered. Variants of the hybridization of energy storage were studied from the standpoint of minimizing the weight, size, and cost indicators. It was established that reducing the mass of the energy storage device, which includes lithium cells and supercapacitors, leads to an increase in the cost of one kilowatt-hour of energy storage capacity, which reduces the attractiveness of capital expenditures for the creation of such an energy storage device. Hybridization of the energy storage device by combining lithium cells of different types practically does not improve its weight, size, and cost indicators. The recommended option is a storage capacity of energy based on LTO elements, for which it is necessary to select elements in order to minimize weight, size, and cost indicators. [ABSTRACT FROM AUTHOR]

The paper deals with the detection process of energy loss in electric railway hauling vehicles. The importance of efficient energy use in railways and cost-effective rail transport tendency toward regenerative braking energy are considered. In addition, the current situation and improvement opportunities to achieve efficient energy use are examined. Seven measurement series were performed with scheduled Railjet trains between Hegyeshalom and Győr railway stations in Hungary. This railway section is related to the Hungarian State Railways' No. 1 main railway line (between Budapest-Kelenföld and Hegyeshalom state board), which is a part of the international railway line between Budapest and Vienna (capitals of Hungary and Austria, respectively). This double-track, electrified railway line with traditional ballasted superstructures and continuously welded rail tracks is important due to the international passenger and freight transport between Germany, Austria, and Hungary. The value of the regenerative braking energy can be even 20-30% of the total consumed energy. This quite enormous untapped energy can be used for several aims, e.g., for comfort energy demand (air conditioning, heating-cooling, lighting, etc.) or energy-intensive starts. The article also investigates the optimization of regenerative braking energy by seeking the energy-waste locations and the reasons for the significant consumption. The train operator's driving style and habit have been identified as one of the main reasons. Furthermore, train driver assistance systems are recommended to save energy, which is planned for future research. [ABSTRACT FROM AUTHOR]

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In the field of heavy-duty transportation of electric locomotives, the power of traction converters can reach MW, but the switching frequency needs to be kept at several hundred Hz. In addition, the converter needs to maintain a high transient response to load changes and keep grid-side harmonics at a low level, which is difficult to meet simultaneously. More critically, load disturbances often occur in electric locomotives during operation, which may lead to DC voltage pulsations and more serious overvoltage faults, which in turn lead to an increase in grid harmonics and a reduction in the stability of the traction system. To address the above challenges, this paper proposes a state observer-based power feedforward control method for high-power locomotives, which helps to improve the dynamic performance of the converter while minimizing harmonics to the grid, thus achieving more stable operation of the traction system. Finally, the feasibility and effectiveness of the proposed method are verified by simulations and multi-condition experiments on a 1.2MW electric traction platform.

The improvement of the energy efficiency of an electric locomotive for railway quarry transport with a multi-motor traction electric drive while disconnection of the traction electric motors has been investigated. Mathematical models of the movement of the train on the track section and during manoeuvring, as well as the model of the energy exchange processes in the traction electric drive, which are used to perform the traction task when the train moves on the track section, have been developed. Through mathematical modelling, the calculation of energy during movement on the track section was performed with all connected and partially disconnected electric motors. When part of the electric motors are disconnected, the energy consumption is reduced by 10% for the cargo half-passage, and by 27% for the empty direct passage. The reduction of energy consumption with disconnected electric motors during manoeuvring has been noticed. The obtained results confirm the expediency and necessity of conducting research aimed to increase the energy efficiency of the multi-motor traction electric drive of an electric locomotive for railway mining transport.

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.

Carbody hunting stability has attracted more and more attention due to its great influence on the dynamic performance of a railway vehicle. To fully understand the correlation between the wheel–rail contact relationship and the carbody hunting stability of an electric locomotive, the wheel–rail contact geometry analysis and the multi-body dynamics simulation are carried out in this work. The focus is on the influences of track parameters (including rail profile, rail cant and track gauge) on wheel–rail contact relationships and carbody hunting stability. A group of rail profiles are obtained by interpolating between the standard CHN60 profile and the worn rail profiles. The nominal equivalent conicity, the effective equivalent conicity and the wheel–rail contact bandwidth for a wheelset lateral displacement of ±6 mm are used to evaluate the wheel–rail contact relationship, while the lateral continuous comfort index is used to evaluate the carbody hunting stability. The simulation results show that keeping the rail cant at about 1/40 and reducing the track gauge and the wear depth at the gauge corner of rail can improve the carbody hunting stability of the electric locomotive. Furthermore, the effective equivalent conicity is a good choice to establish the relationship between the wheel–rail contact geometry and the carbody hunting stability. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There is a plethora of methods in the global literature that can be used to measure CO2 emissions from electrified transport. But are these methods reliable, and do they offer us a true view of how much exactly of this greenhouse gas is being produced by electric rail transport? We answer this question by proposing an improved CO2 emission estimation model based on cargo transport. Unlike other works, our studies include four crucial steps: (1) estimation of energy consumption in electrified rail cargo transport; (2) estimation of energy losses in the railway traction system and high voltage transmission lines; (3) CO2 emission estimation in traditional powerhouses; and (4) determination of the intensity of the CO2 emissions from electrified rail cargo transport. Based on our method, we concluded that the intensity of CO2 depends not only on the type of fossil fuel used for energy production but also on the parameters of the cargo train, such as its length and weight or the total number of wagon axles (which depend on wagon type). The achieved intensity of CO2 emissions in electrified rail cargo transport slightly varies from those reported in the global literature. Among the most important reasons responsible for this are the conditions under which these tests were conducted. Nevertheless, our results shed new light on how CO2 should be measured. We proved that the decarbonization of electrified rail cargo transport will never be possible without infrastructure modernization. In addition, based on a case study, we also delivered knowledge on how to reduce the environmental impact of electrified rail cargo transport.

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.

To improve the conditions of coupling of the wheels of electric locomotives with rails it is proposed to use traction motors with independent excitation. For this purpose, it is proposed to use controlled excitation converters shunting each excitation winding in the power circuit of a single-phase dc electric locomotive. The power scheme of an electric locomotive and a mathematical model of the electric locomotive power circuit, which allows performing research on the operation of a controlled excitation converter, are given. The results of mathematical modeling of electromagnetic processes during operation of a controlled excitation converter in the normal excitation mode and in recharge and discharge modes are presented. The proposed solution provides smooth continuous control of the excitation currents of traction motors in independent and sequential excitation modes without breaking the power circuit and losing the traction. [ABSTRACT FROM AUTHOR]

This article presents a new method for the estimation of active power losses based on a "field" approach, i.e., on the theory of the electromagnetic field and the theory of propagation of electromagnetic waves in a dielectric medium. Electromagnetic waves are assumed to transmit energy from the traction substation to electric rolling stock through the airspace of the inter-substation zone (i.e., not through the wires of the traction network) and meet electrically conductive surfaces on their way. The waves are partially reflected from the surfaces and partially penetrate them, thus creating thermal losses, the determination of which is the main task of this article. The analytical expressions for specific losses of active power are obtained by solving the system of Maxwell's equations. Calculations of specific power losses in the catenary, rails, roofs, and bottoms of carriages and electric locomotives are performed. Power losses in carriages and electric locomotives are found to be at least 7%. A comparative assessment of the magnitude of total power losses of different types obtained by the "field" and "circuit" approaches is provided, which has established that "conditional" losses correspond to losses in rails, train carriages, and electric locomotives. [ABSTRACT FROM AUTHOR]

With the improvement of railway running speed, the safe running of locomotive and rolling stock is particularly important. At present, China has built a series of world-leading high-speed railways with speeds of 350Km/h. With the increase of high-speed train running speed and actual traction capacity, higher requirements for high-speed railway operation safety are put forward. Braking is a very important problem for electric locomotive whether it is in the process of high speed or heavy load. At present, the braking devices of electric locomotives are mainly cast iron brake shoes, which are made of cast iron or other materials to produce braking force through the mechanical friction between the brake shoes and the wheel tread. However, there is no detection of brake working condition in the online detection of electric locomotive operation. This paper analyzes the technical research status of brake shoe of electric locomotive, and analyzes the shortcomings of existing technology. Based on the current technical background, a monitoring system for brake shoe of electric locomotive is designed, which provides a firm foundation for reliable braking of electric locomotive. [ABSTRACT FROM AUTHOR]