Locomotive operation mode - the basis for developing the requirements for the energy storage device on railway transport

Increasing the efficiency of cargo transportation by rail is not only one of the main directions of the company JSC “Russian Railways” but also one of the main tasks of our country in order to achieve sustainable economic growth. Electric rolling stock is the largest consumer of electric energy in the company, that’s why its effective and failure-free operation is the way to solve the set tasks. The paper deals with studies related to the operation modes of a freight electric rolling stock of direct current for the purpose of determining the requirements for electric energy storage device, since it is the electric rolling stock that determines the daily schedule of electric load. The order of the analysis of experimental trips of freight electric locomotives of a direct current on the basis of cartridges of recorders of traffic parameters installed on the locomotive is determined. On the basis of the analysis of conducted trips, the main requirements for the energy storage device were obtained with a single running of electric DC rolling stock, namely the average duration of the operation modes of the electric locomotive, the maximum, minimum, and average values of voltage and current, the average value of the electric energy returned to the contact network, time of charge/discharge, and the useful energy intensity of the electric energy storage device. The studies were carried out with the support of the Russian Foundation for Basic Research for the project No 17-20-01148 ofi_m_RZD/17

Approaches to Creating a Driver Decision Support System for Digital Analysis of Railway Infrastructure Based on Machine Learning and Machine Vision Algorithms

The paper considers the issues of creating a driver decision support system for digital analysis of the railway infrastructure based on machine learning and machine vision algorithms, which will take into account and analyse the given traffic schedule, infrastructure capabilities, dispatch centre teams, statuses of the nearest traffic participants for unmanned safe control of electric rolling stock. A detailed review of existing control systems in railway transport is made, which are based on technical vision

Mathematical Modeling on Statics and Dynamics of Aerostatic Thrust Bearing with External Combined Throttling and Elastic Orifice Fluid Flow Regulation

As aerostatic bearings are used in high-speed metal-cutting machines to increase machining accuracy, there is the need to improve their characteristics, including compliance, which is usually high. In practical applications, a significant reduction of bearing compliance is often necessary, sometimes down to zero and even negative values, to ensure automatic compensation of the elastic deformation in the machine technological system. A decrease in compliance leads to deterioration in the dynamic performance of the bearing, so it is necessary to develop new designs that meet the above requirements. This article considers an aerostatic bearing, in which decrease in compliance is ensured by the use of air throttling with elastic orifices. To ensure its stability, the principle of combined external throttling was applied, which can substantially improve the dynamics of conventional aerostatic bearings. A mathematical model of the elastic orifice deformation was developed, together with the flow rate performance calculation method. The method ensured full qualitative and satisfactory quantitative agreement with the experimental data. The model was used in the mathematical modeling of the aerostatic bearing movement. The article also proposes a method to calculate the static load capacity and compliance of a bearing, as well as a numerical method for fast computation of its dynamic performance, which allows for real-time multi-parameter optimization by the bearing dynamic performance criteria. The study showed that there is an optimal set of design parameters for which low, zero, and negative static compliance of the bearing is ensured, with the necessary stability margin, high speed, and the non-oscillatory nature of the transient processes

Increase of energy efficiency of electric traction system in operating condition of sectioning posts with electric energy storage units

The increase of energy efficiency of the electric traction system is directed to achieving the target indicators, denoted by the Energy strategy of the OS «RZD». One of the basic problems, which must be solved, is the increase of efficiency of the regenerative braking on the railway sections. This could be achieved by receiving regeneration energy. One of the possible decisions is the disposal of the electric energy storage unit in the electric traction system on the sectioning post. For some energy parameters, the installation of storage unit on the sectioning post is more effective in comparison with its location on the traction substations. The analysis of the basic methods of the electric traction system operation when the regenerative braking is applied allows determining the required parameters and finding more effective areas for using the device. The aim of the research is to evaluate the expediency and the efficiency of applying the capacitive energy storage units on the railway posts of the DC sectioning to increase the efficiency of using the regenerative braking as well as to increase the energy efficiency of the electric traction system. Research methods: the simulation modeling of the traction capacity in the electric traction system based on the experimental date, obtained from the measuring system of the DC electric locomotive. Results. The authors have analyzed the influence of the capacitive energy storage units, located on the sectioning posts on the operation modes of the DC electric traction system when the regenerative braking is applied. The electric energy storage unit operation was modeled for one of the actual area of the railroad with several areas between substations, on the base of the data, obtained by the results of processing the goods train traction load. The cross-section of a road includes gradients up to 10 ppm, that causes the wide use of the regenerative braking. The authors proposed the algorithm of controlling the operating mode of the electric energy storage unit on the post of the DC sectioning, which is based on measuring voltage level on the wires of the post of the DC sectioning and on the wires of the electric energy storage unit; considered the diagram of controlling the energy storage units with the counter turning on of the election keys, which provides the energy storage charge unit when using the trains with regenerative braking and its discharge at minimal voltage in the wires of the sectioning post by the maximal traction load. It was shown, that the use of the electric energy storage units on the post of the DC sectioning allows increasing the average voltage on the wires of the adjacent traction substations, reducing electric energy losses in the traction system, the level of the traction load of the converting unit input and the total electric power consumption, determined by the connections of the contact network of the traction substations. The authors estimated the influence of the storage unit on the working parameters of the electric traction system. The paper mentions the defects of the considered diagram of the energy storage unit connection to the wires of the DC sectioning post. The defects can be removed by improving the control diagram

Increase of energy efficiency of electric traction system in operating condition of sectioning posts with electric energy storage units

The increase of energy efficiency of the electric traction system is directed to achieving the target indicators, denoted by the Energy strategy of the OS «RZD». One of the basic problems, which must be solved, is the increase of efficiency of the regenerative braking on the railway sections. This could be achieved by receiving regeneration energy. One of the possible decisions is the disposal of the electric energy storage unit in the electric traction system on the sectioning post. For some energy parameters, the installation of storage unit on the sectioning post is more effective in comparison with its location on the traction substations. The analysis of the basic methods of the electric traction system operation when the regenerative braking is applied allows determining the required parameters and finding more effective areas for using the device. The aim of the research is to evaluate the expediency and the efficiency of applying the capacitive energy storage units on the railway posts of the DC sectioning to increase the efficiency of using the regenerative braking as well as to increase the energy efficiency of the electric traction system. Research methods: the simulation modeling of the traction capacity in the electric traction system based on the experimental date, obtained from the measuring system of the DC electric locomotive. Results. The authors have analyzed the influence of the capacitive energy storage units, located on the sectioning posts on the operation modes of the DC electric traction system when the regenerative braking is applied. The electric energy storage unit operation was modeled for one of the actual area of the railroad with several areas between substations, on the base of the data, obtained by the results of processing the goods train traction load. The cross-section of a road includes gradients up to 10 ppm, that causes the wide use of the regenerative braking. The authors proposed the algorithm of controlling the operating mode of the electric energy storage unit on the post of the DC sectioning, which is based on measuring voltage level on the wires of the post of the DC sectioning and on the wires of the electric energy storage unit; considered the diagram of controlling the energy storage units with the counter turning on of the election keys, which provides the energy storage charge unit when using the trains with regenerative braking and its discharge at minimal voltage in the wires of the sectioning post by the maximal traction load. It was shown, that the use of the electric energy storage units on the post of the DC sectioning allows increasing the average voltage on the wires of the adjacent traction substations, reducing electric energy losses in the traction system, the level of the traction load of the converting unit input and the total electric power consumption, determined by the connections of the contact network of the traction substations. The authors estimated the influence of the storage unit on the working parameters of the electric traction system. The paper mentions the defects of the considered diagram of the energy storage unit connection to the wires of the DC sectioning post. The defects can be removed by improving the control diagram

Theoretical Investigation on Performance Characteristics of Aerostatic Journal Bearings with Active Displacement Compensator

Active aerostatic bearings are capable of providing negative compliance, which can be successfully used to automatically compensate for deformation of the machine tool system in order to reduce the time and improve the quality of metalworking. The article considers an aerostatic radial bearing with external combined throttling systems and an elastic displacement compensator, which is an alternative to aerostatic bearings with air flow rate compensators. The results of the mathematical modeling and theoretical research of stationary and nonstationary modes of operation of bearings with slotted and diaphragm throttling systems are presented. A counter-matrix sweep method has been developed for solving linear and nonlinear boundary value problems in partial derivatives with respect to the function of the square of the pressure in the bearing gap and inter-throttling bearing cavities for any values of the relative shaft eccentricity. A numerical method is proposed for calculating the dynamic quality criteria, and the transfer function of the dynamic compliance of a bearing with small displacements is considered as a linear automatic control system with distributed parameters. An experimental verification of the theoretical characteristics of the bearing was carried out, which showed a satisfactory correspondence among the compared data. It is shown that bearings with a throttle system have the best quantitative and qualitative load characteristics. The possibility of optimal determination of the values of a number of important parameters that provide the bearing with optimal performance and a high stability margin is established. It is shown that bearings with an elastic suspension of the movable sleeve allow one to compensate for significant movements, which can be larger than the size of the air gap by an order of magnitude or more. In these conditions, similar bearings with air flow compensators would be obviously inoperative

Increase of energy efficiency of electric traction system in operating condition of sectioning posts with electric energy storage units

Повышение энергетической эффективности работы системы тягового электроснабжения направлено на достижение целевых показателей, обозначенных Энергетической стратегией ОАО «РЖД». Одной из основных задач, требующих решения, является повышение эффективности рекуперативного торможения на участках железных дорог, что может быть достигнуто обеспечением приема энергии рекуперации. Одним из возможных решений является размещение накопителя электрической энергии в системе тягового электроснабжения на посту секционирования, так как по ряду энергетических параметров именно на посту секционирования установка накопителя оказывается более эффективно по сравнению с размещением на тяговых подстанциях. Изучение основных режимов работы системы тягового электроснабжения в условиях применения рекуперативного торможения позволяет определить необходимые параметры и найти наиболее эффективные участки применения устройств. Цель работы: оценка целесообразности и эффективности применения емкостных накопителей электрической энергии на постах секционирования железных дорог постоянного тока, в целях повышения эффективности применения рекуперативного торможения, а также повышения энергетической эффективности системы тягового электроснабжения. Методы исследования: имитационное моделирование тяговой нагрузки в системе тягового электроснабжения на основе экспериментальных данных, полученных с измерительных систем электровозов постоянного тока. Результаты. Исследовано влияние емкостных накопителей энергии, расположенных на постах секционирования, на режимы работы системы тягового электроснабжения постоянного тока в условиях применения рекуперативного торможения. Моделирование работы накопителей энергии выполнено для одного из реальных участков железной дороги, содержащих несколько межподстанционных зон, на основе данных, полученных по результатам обработки тяговой нагрузки грузового поезда. Профиль пути рассматриваемого участка железной дороги содержит уклоны до десяти промилле, что обусловливает широкое применение рекуперативного торможения. Предложен алгоритм управления режимами работы накопителя электроэнергии на посту секционирования постоянного тока, основанный на измерениях уровня напряжения на шинах поста секционирования постоянного тока и шинах накопителя энергии. Рассмотрена схема управления накопителями энергии со встречным включением электронных ключей, обеспечивающая заряд накопителя энергии при применении поездов рекуперативного торможения и его разряд при минимальном напряжении на шинах поста секционирования при максимальной тяговой нагрузке. Показано, что применение накопителей энергии на посту секционирования постоянного тока позволяет повысить среднее напряжения на шинах смежных тяговых подстанций, сократить потери электроэнергии в тяговой сети, уровень тяговой нагрузки по вводу преобразовательного агрегата и суммарный расход электроэнергии, определяемый по присоединениям контактной сети тяговых подстанций. Выполнена оценка влияния накопителя на параметры работы системы тягового электроснабжения. Отмечены недостатки рассматриваемой схемы подключения накопителя электроэнергии к шинам поста секционирования постоянного тока, которые могут быть устранены в дальнейшем путем совершенствования схемы управления.The increase of energy efficiency of the electric traction system is directed to achieving the target indicators, denoted by the Energy strategy of the OS «RZD». One of the basic problems, which must be solved, is the increase of efficiency of the regenerative braking on the railway sections. This could be achieved by receiving regeneration energy. One of the possible decisions is the disposal of the electric energy storage unit in the electric traction system on the sectioning post. For some energy parameters, the installation of storage unit on the sectioning post is more effective in comparison with its location on the traction substations. The analysis of the basic methods of the electric traction system operation when the regenerative braking is applied allows determining the required parameters and finding more effective areas for using the device. The aim of the research is to evaluate the expediency and the efficiency of applying the capacitive energy storage units on the railway posts of the DC sectioning to increase the efficiency of using the regenerative braking as well as to increase the energy efficiency of the electric traction system. Research methods: the simulation modeling of the traction capacity in the electric traction system based on the experimental date, obtained from the measuring system of the DC electric locomotive. Results. The authors have analyzed the influence of the capacitive energy storage units, located on the sectioning posts on the operation modes of the DC electric traction system when the regenerative braking is applied. The electric energy storage unit operation was modeled for one of the actual area of the railroad with several areas between substations, on the base of the data, obtained by the results of processing the goods train traction load. The cross-section of a road includes gradients up to 10 ppm, that causes the wide use of the regenerative braking. The authors proposed the algorithm of controlling the operating mode of the electric energy storage unit on the post of the DC sectioning, which is based on measuring voltage level on the wires of the post of the DC sectioning and on the wires of the electric energy storage unit; considered the diagram of controlling the energy storage units with the counter turning on of the election keys, which provides the energy storage charge unit when using the trains with regenerative braking and its discharge at minimal voltage in the wires of the sectioning post by the maximal traction load. It was shown, that the use of the electric energy storage units on the post of the DC sectioning allows increasing the average voltage on the wires of the adjacent traction substations, reducing electric energy losses in the traction system, the level of the traction load of the converting unit input and the total electric power consumption, determined by the connections of the contact network of the traction substations. The authors estimated the influence of the storage unit on the working parameters of the electric traction system. The paper mentions the defects of the considered diagram of the energy storage unit connection to the wires of the DC sectioning post. The defects can be removed by improving the control diagram