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This article is devote to the development of software for analyzing and transforming data from studies of the collector surface traction motors using a device of control profile commutator PKP-4M. The use of this computer application during the processing of the experimental data will improve the reliability of the control profile of the commutator, and to calculate the main diagnostic parameters characterizing the effect of the profile on the commutation process.

Analysis of the causes of errors of measurement of phase shifts of harmonic components in electrical railway traction networks and describes how to improve the accuracy of measurement.

The paper presents a comparative analysis of different methods of quantization of continuous signals, including optimal with the maximum entropy and the entropy – suboptimal, with various parameters of signal distribution.

Is executed the analysis of the permissible range of the fluctuation of the phase of signal on the entrance of digital measuring device with a study of phase relationships in the tractive networks of the power supply of rail transport, characterized by high noise level.

In the work completed a study of shape vertices a unimodel probability density function (kurtosis) on the output of the nonlinear converter «phase shift - code, which is the most important parameter for evaluating conditions of finding mode to this function. To increase the accuracy of assessment shifts phases when there is high level of random noise is defined not only quality, but also quantitative dependence of the kurtosis probability density function on the output of the nonlinear converter «phase shift - code» of Standard deviation phase fluctuations of the signal at its input. The mathematical model of the distribution function on the output of the converter «phase shift - code» for research and implementation of algorithms improve noise immunity measure phase shifts between harmonic components of voltage and current in traction power supply rail transport networks.

In work done modeling and analysis of noise immunity of the proposed measurement method of phase shifts between harmonic components of voltage and current in traction power supply rail transport networks and estimation of maximum permissible noise level, where workability digital devices used to study phase shifts in these conditions. The simulation results have shown that the probability density function on the output of the nonlinear converter «phase shift - code» remains a unimode at any ratio range converter and standard deviation of the phase of the input signal. Implementation of researched ways of microprocessor-based digital device guarantees the stability and accuracy of measurement results in traction phase shifting networks of power supply of railway transport in the presence of high levels of industrial noise, nonlinear fast variable nature of the traction load, sparking the pantographs for electric locomotives in contact network and use recovery systems based on pulse converters.

The article shows the relevance of the problem of noise pollution of the environment by railway transport. The purpose of the research is to assess by calculation and instrumental methods the compliance of the existing noise levels in the residential area near the railway tracks with sanitary standards, to propose a set of noise protection measures and to substantiate their acoustic efficiency. The applied methods for measuring and calculating the equivalent and maximum noise levels of the rolling stock comply with the requirements of regulatory documents. The authors took into account the features of the propagation and shielding of sound waves in the existing residential area, background noise, and the traffic intensity of trains of various categories. The results of measurements, calculations and estimates of the noise generated by the rolling stock in the residential area in Omsk are presented. A significant excess of the maximum permissible equivalent and maximum noise levels in residential areas has been established. Comparison of the calculated and measured noise values, taking into account the standard uncertainty of the calculation methods and the expanded measurement uncertainty, showed quite satisfactory convergence of the results obtained and confirmed a significant excess of the sanitary noise standards. A set of measures is proposed to reduce the noise of railway rolling stock at the source of its occurrence and on the path of its propagation in the existing residential area. The dimensions of the embankments of the two sections of the railway tracks allow the installation of screens of low height up to 38 cm, the geometry of which is designed so that, in terms of reflection of the noise emitted by the rolling stock, they are at least equivalent to a standard noise protection wall 2 m high. For the track section located in the recess, it is proposed to install a noise barrier 6 m high and at least 1 km long. Its acoustic efficiency was calculated.

Developed Methodology let make the calculation of coaxial cable parameters with account of the frequency of the transmitted signal. The comparative analysis of parameters of RC 50-7-28 and RG142 cables has been made with the values have been got by the measuring with the circuit analyzer according to the reference book with the results of the calculations. Check the accuracy of the calculation has pointed out the necessity for account of complementary factors for the purpose of much more correct account cable attenuation in the frequency spectrum.