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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 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.

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.