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The urgency of the task of creating test signals of vibration. Described possible ways of implementation of the test vibration signals. A method of forming a test signal by adjusting amplitudes of the individual harmonic components of the vibration signal. Showing the results of modeling. Shows the possible effect of using the proposed method.

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.

The article presents the main requirements for the development of traction motors commutation control digital device and the results of the development and testing of this device on the test bench. Justified the expediency of application of the input highpass filter when the power of the testing traction engine from the thyristor converter. Presented the technique of processing the diagnostic signal from bipolar brushes to filter out noise of different physical nature.

This paper considers a continuous automatic locomotive signalling (CALS) receiver with a correlation decoder. The aim of this paper is to investigate the influence of harmonic interference from a high-voltage power line on the operation of a non-linear CALS receiver with a correlation decoder. The experimental study of the quality of operation of a non-linear CALS receiver with a correlation decoder under the influence of harmonic interference from high-voltage power lines was carried out using the simulation method. Simulation models of interference from a high-voltage power line (VPL), a receiver and a correlation decoder of the CALS channel were used in the study. The analysis of oscillograms obtained as a result of the study has shown that the correlation decoder has a number of features due to the algorithm of its functioning. The correlation decoder more confidently accepts code combinations with a duration of 1.6s (generated by the code track transmitter of CTT-5 type), than the duration of 1.86s (generated by the code track transmitter CTT-7). This is expressed in a shorter time interval of disturbance of the CALS non-linear receiving device. At decoding of the code combination (CC) with the duration of both 1.6 s and 1.86 s the situation of short-term decoding of the more permissive CC «Y» instead of «RY» was observed. However, the duration of these situations did not exceed two code cycles and would not have caused a more permissive light to appear at the locomotive traffic light. In general, the experiments have shown that the CALS CC correlation decoding algorithm needs improvement for more confident decoding of CCs produced by a code track transmitter of the CTT-7 type(1.86 s).

The minimum of number of operations for a polynomial calculation is found. Results are presented as proofs of one lemma and one theorem.

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 article covers stability and accuracy for restoration of uneven sampled signals, using basis functions. The accuracy and stability are explored for different transfer system orders, period between basis functions and offset of the basis functions system against restored samples.

The article presents statistical studies of acoustic control signals when diagnosing power transformers of the railway power supply system. Statistical processing of acoustic monitoring data was carried out on the example of transformers with different levels of insulation condition. Comparisons of histograms of the experimental distribution of amplitudes and dominant frequencies of signals with the nearest theoretical distribution laws, performed in the STATISTICA program according to control data obtained from the automated system. The conducted studies have shown a close correlation of defects registered by the acoustic method with the distribution of signals in the form of laws of distribution of random variables. It is shown that for power transformers with mechanical oscillations, both during the passage of the train and at idle, the distribution of amplitudes and dominant frequencies of the recorded signals corresponds to a uniform law. The distribution of amplitudes and dominant frequencies is not centered around a certain average value. For power transformers containing partial discharges, the cause of which is the deterioration of the insulating properties of the windings under the influence of high voltage, the best approximation, both amplitudes and dominant frequencies, showed the Lognormal distribution. The signals are centered around a characteristic mean value. When the train passes, the acoustic system registers both high-frequency signals from the PD and low-frequency signals from body vibrations. There are two components in the distribution law - uniform and lognormal distribution densities. Thus, by the type of distribution of the recorded signals, their amplitude and dominant frequency, it is possible to determine the presence of a defective state of the insulation of power transformers. The study was carried out with the financial support of the Russian Foundation for Basic Research within the framework of the scientific project No. 20-38-90231.

Example of the methods to evaluate conditions and reserve of transverse stability in CWR curves under abnormal track maintenance is discussed in the article. The author presents the results of the research of this method and also its positive effect is described.

In microprocessor automatic block signalling (ABS) systems all the basic functionality is implemented in software. Current technique used by Russian educational organisations for training of engineering staff is solely based on functionality exploration of the microprocessor ABS equipment. We suggest that this approach is not sufficiently effective and could be improved. In our view, the improvement could be achieved by addition of extensive ABS algorithm development practice to the Railway Signalling Engineering curriculum. In this article, we present a prototype of a special microprocessor learning board, which supports development and debugging of various ABS algorithms. Along with the functional diagram, we give some technical details and present preliminary results of implementing and using this prototype.

This article discusses a modern method for diagnosing track circuits using broadband signals. The relevance of this research stems from significant shortcomings of traditional track circuits, such as low information content, strong dependence on ballast condition, and high operating costs, which lead to significant economic losses and risks to traffic safety. The proposed approach using broadband signals enables continuous monitoring of track conditions in real time, precisely localizing defects such as breaks, current leaks, insulation deterioration, and microcracks, which is impossible using traditional methods. This not only improves traffic safety but also significantly reduces the number of false alarms. The paper presents a detailed mathematical model of broadband signal propagation, taking into account key attenuation factors: the effect of current leakage through ballast, sleepers, and track connections. A comprehensive analysis of the signal's frequency characteristics was conducted, including a study of the skin effect in rails and the dependence of the complex ballast impedance on external conditions such as humidity and temperature. To minimize signal loss, a comprehensive approach based on adaptive frequency range optimization and data processing algorithms was proposed. The study focuses on the principle of matched filtering, which maximizes the signal-to-noise ratio at the filter output through effective signal compression and intelligent parameter selection. A structural diagram of the diagnostic system with a detailed description of its functional components was developed and presented. The study results demonstrate that the implementation of a monitoring system based on broadband signals enables continuous monitoring of infrastructure conditions without interrupting service, significantly improving the accuracy and speed of defect localization. Practical implementation of the developed method can significantly reduce operating costs and improve the overall reliability, safety, and throughput of rail transport.