Journal of Transsib Railway Studies V.4(64), 2025

The paper discusses the design and principle of operation of the elastic-friction absorbing device of the automatic coupler. The results of a study of the force characteristic of the elastic-friction absorbing device of the automatic coupler, which takes into account the operating modes of the device and the deformation of the structural elements involved in the transmission of longitudinal force from the automatic coupler body to the absorbing device, are presented. It is proposed to consider the force characteristic of the absorbing device as a piecewise linear loop characteristic consisting of nine sections. Equations have been obtained for determining the static force characteristic for each deformation section of the corresponding structural element of the absorber apparatus of the automatic coupler. The force characteristic has been described using a single system of equations. The main numerical parameters characterizing the operation of the absorber apparatus, such as the stiffness and deformation of the structural elements of the apparatus, the automatic coupler body, and the spring, have been refined and determined. The developed mathematical model of the spring-friction absorber of the automatic coupler takes into account all modes of its operation and deformation of the structural elements that transmit the longitudinal force from the automatic coupler body to the absorber. The results obtained in the work specify the form of the power characteristic of the absorbing device, bringing it closer to the experimentally obtained graphs. The presented mathematical description of the power characteristic can be used in the development of a multi-mass train model, which is a system of rigid bodies connected to each other by nonlinear elastic-frictional bonds. The results of this study can be used to determine the maximum forces in the absorbing devices of automatic couplers when modeling longitudinal vibrations in freight trains, which occur when the locomotive operating modes and train movement modes change as the train passes through the longitudinal track profile changes.

Subject, purpose of work: This article analyzes the mechanical response of block compensator systems in overhead contact wires to mass increments from ice accretion. The work formally describes force interactions in two-block and three-block configurations and determines the sensitivity of reaction forces at attachment points to localized weight increases. Method or methodology: Using static equilibrium equations and geometric relationships, the study derives expressions for calculating compensator support forces while varying conductor mass and parameters. The analysis provides detailed formulas for reaction forces, deflection angles, and horizontal tension components. Through linearization, we establish sensitivity estimates for system response to small mass increments modeling initial ice formation stages. Work results: We demonstrate that increasing the number of blocks fundamentally alters force equilibrium structure and produces distinctly different sensitivity values. The study derives mathematical expressions enabling calculation of compensator support forces under varying conditions. Scope of results: The results enable practical applications in force sensor placement, weight measurement algorithms, engineering calculations for tension sections, and contact suspension behavior modeling under variable loading conditions. Conclusions: Our findings substantiate the effectiveness of mathematical block compensator models for quantitative diagnostics of overhead contact wire systems during winter operations and establish the methodological foundation for further research investigations.

The reliable operation of a locomotive's diesel engine depends on the efficiency and quality of the cooling system, therefore, it is important to maintain optimal performance throughout the entire period of operation. The cooling system is developed individually for each type of diesel engine, therefore, when designing new diesel generator sets for locomotives, it is necessary to improve cooling systems, which is one of the most important tasks of ensuring reliable and efficient operation, while it is important to use test complexes to simulate real-world work processes, to obtain estimated capabilities and optimize thermal conditions. This scientific paper presents the results of the development and operation of a stand for simulating the operation of a cooling system, with the possibility of simulating various operating modes. The research is based on the method of physical modeling of thermal processes using controlled heat load sources and a system of control and measuring devices. The experimental installation is equipped with a cooling circuit system with adjustable operating parameters. The developed stand makes it possible to carry out resource tests of cooling system elements, optimize algorithms for controlling thermal conditions and determining the amount of heat generated and discharged from the system, as well as with the ability to work out troubleshooting methods without using standard diesel equipment. The practical significance of the stand is the possibility of creating methods for a comprehensive assessment of the dynamic characteristics of the cooling system with the possibility of modeling emergency situations and investigating transient processes of heat flow redistribution simulating real processes. During the operation of the stand, it is possible to install a comprehensive assessment of the performance of the cooling system, taking into account heat dissipation, the amount of heat removed, and heating-cooling intensity indicators when simulating work with different amounts of water circuits. The application of the research results may be useful in the development of new and modernization of existing diesel cooling systems, as well as in the study of heat dissipation during operation of locomotives in winter, when it is important to preserve heat in the system.

This paper investigates the issue of voltage distortion in the 0.4 kV power supply at electric centralization (EC) posts. Significant voltage distortion may trigger an emergency switch to the backup feeder, potentially leading to failures in railway automation and telemechanic systems. To analyze this problem, a series of field measurements were conducted to assess the quality and harmonic composition of the supply voltage at an EC post. The experimental results revealed a direct correlation between the degree of voltage distortion and the load current on the adjacent traction substation. Using computer simulation tools, a detailed model of the traction substation, including the power supply lines to the EC post, was developed. Based on this model, optimal parameters for a passive LC filter tuned to suppress the 11th and 13th harmonic components - dominant under the 12-pulse rectification scheme - were calculated. A prototype harmonic filter was then constructed and integrated into the power supply line of the EC post. Post-installation field measurements were carried out to evaluate the voltage quality improvement. The results confirm the effectiveness of the selected filter in reducing both the total harmonic distortion (THD) of the voltage and the individual harmonic components of the 11th and 13th orders. During the entire four-month trial operation period, no emergency power transfers were recorded at the EC posts. The findings of this study can be applied to similar systems within DC-electrified railway networks, taking into account variations in rectification schemes and non-traction load power supply configurations.

In the modern operating conditions of railway refrigerated transport, the primary tasks have become increasing the energy efficiency of rolling stock and reducing operating costs. This article presents an analysis of the energy and economic efficiency of replacing the power equipment of an autonomous refrigerated car to transition from diesel fuel to liquefied natural gas. To perform the analysis, the authors developed an engineering model of the energy balance for the autonomous refrigerated car equipment, supplemented by a cold recovery loop from liquefied natural gas regasification. The research methodology is based on a systems approach that considers the thermodynamic properties of the proposed replacement fuel and the specifics of heat exchange processes in the cargo compartment. Based on the obtained model, a comparative analysis was performed between the calculated indicators of the considered power equipment designed for liquefied natural gas and the operational data of existing diesel analogs. During the evaluation of the fuel replacement effect, the technical feasibility of ensuring standard car autonomy indicators when transitioning to liquefied natural gas without deteriorating the rolling stock's operational characteristics was confirmed. It was established that cold recovery from liquefied natural gas regasification significantly improves the equipment's energy performance, ensuring a sufficient level of energy autonomy and reduced fuel consumption through the beneficial use of the gas's physical exergy. The developed model allows for a comprehensive assessment of the systemic effect of replacing diesel fuel with liquefied natural gas, taking into account various temperature regimes of the car body. The conclusions demonstrate that converting refrigerated rolling stock from diesel fuel to liquefied natural gas for use as both energy fuel and refrigerant (cogeneration) is expedient.

The article examines modern approaches to improving dispatcher centralization (DC) systems through the use of programmable logic controllers (PLCs). An analysis is presented of the structure and functioning of the line station (LS), which incorporates channels for telecontrol (TC), telesignaling (TS), and synchronization (SC). Particular attention is paid to enhancing the reliability of transmitted data by applying cyclic redundancy codes (CRC). The study demonstrates the potential of modeling the states of controlled objects using automata theory, in particular the Moore automaton, which allows for improved predictability of system output characteristics and greater control reliability. Using the Siemens SIMATIC S7-1200 PLC in the TIA Portal environment, fragments of DC logic were implemented in the Ladder Diagram (LD) language. The obtained results demonstrate the effectiveness of applying PLCs in railway automation and confirm the prospects for further integration of intelligent diagnostic algorithms aimed at enhancing train traffic safety. This article presents a comprehensive study of the dispatcher centralization (DC) system, which serves as a key element in ensuring the safety and efficiency of train traffic management on modern railways. The primary focus is on the processes of forming and analyzing discrete signals at line stations (LS), which originate from electrical interlocking (EI) objects such as switches and signals. The study provides a detailed discussion of signal processing algorithms, as well as methods for detecting and diagnosing potential malfunctions - such as false track occupancy or loss of object control - that may lead to operational disruptions. To enhance the reliability and accuracy of object state monitoring, a model based on automata theory, namely the Moore automaton, is proposed. This model enables the formalization and prediction of system behavior under different states, taking into account temporal sequences of signal transitions. To ensure the integrity and reliability of transmitted data between the central and line stations, the use of a noise-resistant cyclic redundancy code (CRC-8) is proposed. The practical part of the research includes the development and simulation of program logic in the Ladder Diagram language within the TIA Portal environment, using the Siemens SIMATIC S7-1200 PLC certified for railway applications. Structural and functional diagrams of the system, state transition tables of the automaton, and signal timing charts are provided. The results are aimed at improving the fault tolerance and uninterrupted functioning of dispatcher centralization systems, which constitutes a key factor in the advancement of future intelligent transport systems.

This article presents a comprehensive methodological framework developed to determine the optimal parameters of railway terminals designed for piggyback transportation in the Republic of Uzbekistan. The main focus is on creating a scientifically grounded approach that combines analytical modeling, statistical evaluation, and spatial analysis. The application of this integrated method enables a systematic, consistent, and data-driven process for selecting terminal locations, defining their technical, operational, and throughput characteristics, and accounting for the economic, infrastructural, and logistical specificities of each region. Within the framework of the study, a detailed rating system was developed to assess the performance and operational efficiency of 18 logistics centers currently functioning across the country. The evaluation criteria included throughput capacity, infrastructure condition, level of multimodal connectivity, transport accessibility, geographical position, potential for future development, and resilience to market fluctuations. The findings revealed that, despite the relatively high operational indicators of the logistics centers located in the Bukhara and Samarkand regions, the Navoi region was identified as the most favorable location for the construction of a new piggyback terminal. This conclusion is explained by the region’s balanced transport network, availability of undeveloped land resources, favorable natural and geographical conditions, and strategically advantageous central position that connects major domestic and international freight corridors. The results of the conducted research have high scientific and practical significance for experts in transport planning, logistics, and public policy, providing a methodological foundation for the sustainable development of intermodal infrastructure in Uzbekistan and the broader Central Asian region.

Subject of research. The study focuses on the industrial transport system of a metallurgical enterprise, specifically on railway traffic management processes and the prospects for implementing microprocessor-based centralization (MPC) as a key element in modernizing railway automation and remote control systems. Objective. To assess the feasibility of deploying MPC at industrial stations of a metallurgical plant. Evaluate the need to replace the existing block route-relay centralization system for train traffic control. Explore modern control systems for railway automation and telemechanics. Identify non-transport benefits of such modernization measures. Methods. Field observations and inspections of the current state of railway automation and telemechanics systems across 19 railway stations of the plant, statistical and objective observations, analytical and deductive methods, comparative analysis of statistical data (traffic volumes, shunting operation intensity, number of failures), technical specifications comparison. Results. The study delivered: identification of ancillary positive effects in industrial transport operations management. Key findings include: a significant reduction in operational costs; confirmed decrease in failure rates at stations equipped with MPC; enhanced reliability due to built-in diagnostic capabilities. Area of application. The results are applicable for: planning modernization of railway automation at industrial railway stations; optimizing operational costs and improving transportation safety; developing methodologies to evaluate the economic efficiency of MPC implementation at enterprises with intensive railway traffic. Conclusions. The research demonstrates that MPC deployment enhances the reliability and resilience of industrial transport systems. This is particularly critical in conditions of increasing turbulence in transport flows and economic relations within the «production-transport-consumption» system.

The reliability and longevity of electrical machines, such as motors and generators, are critically determined by the condition of their insulation system. This paper presents a comprehensive analysis of the multifaceted processes leading to the degradation of winding insulation materials. The study reveals the complex and often non-linear interrelationships between key aging factors thermal overloading, electrical surges, mechanical vibrations, and the detrimental impact of the environment (humidity, contaminants). The combined influence of these factors leads to a progressive deterioration of dielectric strength and, consequently, a reduction in the equipment's service life. As a methodological foundation, an innovative approach to insulation condition diagnostics, based on graph modeling, is proposed. The developed graph model serves as a formalized tool for describing cause-and-effect relationships between input parameters (armature current, voltage, and start/stop regimes), external operating conditions, and internal diagnostic parameters, such as insulation resistance, tangent delta, and partial discharge characteristics. Particular attention in the model is paid to the analysis of positive feedback loops, which explain the non-linear, avalanche-like nature of damage development, where one type of defect accelerates the progression of others. The practical significance of the research lies in the transition from traditional planned-preventive maintenance to a predictive model. The proposed graph model enables the early diagnosis of degradation signs and the construction of accurate forecasts for the insulation's remaining useful life. The results of the work pave the way for the development of intelligent monitoring and diagnostic systems, as well as for the optimization of maintenance strategies for power electrical equipment, ultimately enhancing its operational reliability and economic efficiency. The developed graph model will serve as a theoretical basis for creating effective diagnostic systems and predicting the remaining useful life of insulation. Identifying positive feedback loops in degradation processes makes it possible to determine critical control points and develop preventive measures to prevent sudden failures.

In this research, a formal strategy for enhancing the electronic distribution of technical documents in railway automation and telemechanics is developed. The accounting and control of device-related documents are formalized using a graph-based model. By creating maximally compatible (non-contradictory) groupings of LSA elements, a micro-command system is created using logical scheme algorithm (LSA) A71 as a case study, illustrating how to simplify the logical scheme (LS). In order to characterize the methods for producing the subsequent micro-instruction code and to depict the parallel execution of internal and external micro-operations, matrix representations are introduced. The study thus suggests a useful formal model and graphical approaches for the analysis, synthesis, and assessment of workflows involving electronic technical documents. These methods aim to minimize the number of internal states in logical structures by forming compatible groups of LSA elements. The resulting micro-commands allow the simultaneous execution of multiple micro-operations within a single micro-cycle, thereby increasing processing efficiency. Extended logical schemes were introduced to better assess the complexity of automata used in managing electronic technical documents. A graphical model of the logical schemes is developed, offering practical tools to design and optimize automation processes. The proposed approach simplifies the control structure while maintaining the system’s functionality, allowing for more efficient monitoring and real-time control in railway operations. This methodology is especially relevant for modernizing technical documentation systems used in the transport sector and integrating them with automation and control mechanisms.

The article subject is the maintenance and repair system (MRO) of domestic locomotives in comparison with the European standards requirements in order to harmonize domestic MRO with international requirements. Russian Railways has created an integrated automated control system (ACS), including monitoring and reliability management systems for locomotives. Automated control systems for maintenance and repair of traction rolling stock are created on the service side of locomotive construction. TMH has developed automated control systems for maintenance and repair of traction rolling stock automated control systems for MRO. This system provides accounting for completed cyclic and super-cyclic work, consumed materials, completed installation and dismantling of equipment. An electronic passport of the locomotive has been created. Additionally, an automated control system for locomotive reliability has been created, in which the basic processes are incident and failure management, as well as problem management. The MRO TMX automated control system can be considered a unique development in terms of its functionality and scope. Work is underway to integrate the automated control systems of Russian Railways and automated control systems of service companies. At the same time, the European Union (EU) has been actively working over the past decades to harmonize national standards with interstate ones. A unified technical, economic and legal space is being created gradually. A series of standards has been developed for the management of railway transport, rolling stock and its maintenance. The standards summarize the accumulated experience and contain a number of provisions that could be useful for Russian railways, their traction rolling stock and maintenance organization. The EU standards analysis from the standpoint of improving the quality of domestic locomotives service has been carried out. The analysis showed that, in general, technological approaches in domestic transport comply with the requirements of European standards. But there are fundamental differences - the lack of a competitive environment and transparency of information. It is necessary to correct these shortcomings, which will significantly increase the intellectual potential of engineering. It is advisable to take the results obtained into account when organizing the domestic locomotives MRO.

This article is devoted to the development and validation of a system for monitoring and accounting of railway automation and telemetry equipment using NFC technology. The primary objective of the study is to develop technical systems for the maintenance, repair, and storage of a significant amount of equipment in repair and maintenance areas. To select the optimal technical solution, an analysis of existing technologies was conducted, including barcode, QR code, RFID, and NFC. NFC was chosen because it provides high security and data exchange speed, low power consumption, and resistance to external influences, which is critical for the integrity and reliability of accounting information. The research methodology included creating a conceptual warehouse model and using photographs of the equipment maintenance and repair process to formalize time costs. The analysis identified the most inefficient elements-the receiving (Och2) and shipping (Och4) processes, where manual documentation takes up to 20 minutes per device. The proposed system is a comprehensive solution comprising a central node (a phpMyAdmin database server), specialized information and algorithmic support for the warehouse management system, and NFC tags, which serve as a source of basic and reference information about the equipment. Implementation of the system includes the integration of reader devices and the scheduled application of tags directly to the railway automation equipment. The efficiency assessment was conducted through simulation modeling of the warehouse management system using an agent-based approach in the Anylogic platform. The simulation showed that implementing the system within a single RTU processing 3,020 devices per month will reduce the total annual labor costs at the "Och2" and "Och4" stages from 416 to 52 man-hours. The 364 man-hours saved facilitate the redistribution of the electricians' workload, increase overall labor productivity, and enhance the RTU's processing capacity.

The quality of the transportation process largely depends on the locomotives reliable operation. Therefore, in modern railway transport automated control systems (ACS), it is necessary to establish subsystems for managing the traction rolling stock reliability. Information for reliability management appears and is used by various automated control systems, the interaction between which is provided by an interoperable connection. As a result, a cyber-physical production system (CPPS) is being created based on the fourth industrial revolution «Industry 4.0» principles. The influence of the locomotives technical condition on the quality of the transportation process is determined in the automated Control System "Schedule of completed movement" (GID). Failures recorded on the schedule thread are sent to the reliability management system of Russian Railways KASANT hardware, from where they are transmitted to the service company incident and failure management system. Similarly, the service company receives information about the locomotives operation (mileage) and diagnostic data from on-board locomotives microprocessor systems. Based on these data, as well as data from depot automated technical diagnostics systems, the volume is determined and maintenance and repair (MRO) is carried out - scheduled preventive and unplanned restoration. Work is being assigned, materials are being discharged from the warehouse, and resources are being planned for subsequent MRO. MRO data is used during the initial investigation of the causes of failures, the party responsible for the failure is determined, and the data is transmitted to KASANT in the form of an electronic protocol for analyzing failures. Information about the failure stream is the initial source for eliminating the root causes of system failures after a secondary investigation and determining the root cause. The model implements the principle of continuous improvement (PDCA cycle). Additionally, the control system requires the encapsulation of mathematical control methods.