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The analysis of the influence of operating modes and the development of the residual life, expressed through thermal wear of the insulation of the asynchronous traction motor. The research subject is to obtain new patterns of change in the residual life of the stator winding insulation, which make it possible to determine the specific life of the winding for each mode of the asynchronous traction motor. The research aim is to create a system for determining and assessing the residual life by developing methods and technical means of monitoring and comprehensive diagnostics, as well as theoretical justification using the method for determining additional thermal wear of the stator winding insulation, taking into account the combined effect of the starting transient process, the long-term allowable load schedule and the maximum allowable temperature values. To determine and assess the possible residual life, the method of sequential influence of starting transients, maximum permissible load curves, as well as long-term overloads at the maximum permissible temperature, taking place under various operating factors during the movement of electric rolling stock, was used. The expediency of determining the function of uneven resource development, which has a monotonic character and is approximated by a linear double exponential and exponential functions, is shown. Specific proportionality coefficients are experimentally determined, which characterize the decrease in the dielectric strength of the insulation with sequential alternation of maximum and long-term permissible loads and maximum permissible temperature values, followed by obtaining an analytical relationship that predetermines the insulation resource. It is shown that the determination and assessment of the residual resource under typical modes practically makes it possible to clarify the timing of preventive measures and predict the expected duration of accident-free operation and forestall the premature failure of the asynchronous traction motor.

Electric power installation of a special self-propelled rolling stock used in the power supply divisions is considered in the paper; the expediency of its use for the analysis of the main energy indices, in particular, the evaluation of the efficiency of electro-hydro-mechanical units at separate and joint operation, is shown. To assess the energy efficiency, an integrated efficiency factor has been proposed that allows to account the energy parameters of electrical installations operating in various modes. Recommendations have been given to increase the power factor of electrical installations.

A mathematical model for diagnosing the state of solid insulation of high-voltage transformers based on an informational assessment of indirect indicators, i.e. entropy, for example, by the content of impurities of various gases dissolved in transformer oil, which allows to determine the technical condition without removing the workload. The values of the average information on the working and faulty state of insulation for various types of gas impurities are calculated.