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The article suggests that the reason for the increased wear of the tires of electric locomotives with an asynchronous traction drive is the increased sliding speed in the contact of the wheels with the rails. It is shown that in thrust modes with high sliding speeds, frictional self-oscillations can develop in the drive. The stability zones of the drive are constructed in the space of its parameters. The model of an asynchronous drive with a «jammed rotor» for the study of skidding modes has been substantiated. It is recommended to install a clutch control system (СCS) on the electric locomotive to reduce wear on wheels and rails. СCS intelligent sensors create an additional feedback channel for the system of optimal traction control - the implementation of maximum traction forces with minimal friction losses. The methods and recommendations presented in the article are applicable to various designs of traction drives.

The mathematical model of traction drive Electric locomotive EP20 for research of dynamic processes in a mode of boxing is constructed. The natural frequencies and coefficients of the forms of the dynamic system are determined. The stability of the drive in relation to frictional self-oscillations is estimated. Dynamic loads in the drive elements at a single angular speed of wheel slip are calculated. The recommendations on increasing the dynamic qualities of the traction drive in the sliding mode are formulated.

The wheel-motor unit of freight electric locomotives is characterized by the dynamic effect of a wide range of the disturbances due to irregularities in the track. This is one of the main reasons for the high damageability of the gear casings, observed recently, and it indicates the need to improve its design. The proposed design changes for the casing should be directly related to the assessment of the level of the dynamic loading during its operation. The results of the numerical and experimental determination of the natural frequencies of metal casings of traction gear used on electric locomotives of the VL85 and 2 (3) ES5K series are presented. For the numerical determination of the natural frequencies of the enclosures, a modal calculation of the solid model of the enclosure in the Ansys Workbench software environment was performed using the finite element method. A comparative analysis of the distribution of deformation fields in the sidewalls of the casing for a casing that is not fixed to the traction engine and rigidly fixed is carried out. For the experimental evaluation of the natural frequencies of the gear casings, a vibration transducer fixed on the casing was used; the method of excitation of vibrations with a single blow was used to excite vibration. As the result of the experiment, the peak values of vibration acceleration were revealed at some frequencies, which testifies to the emerging resonance phenomena for the casing, and the values of such dynamic parameters for the casing design as natural frequency, Q-factor of the oscillating system, logarithmic damping decrement, relaxation time were obtained. The values of the natural frequencies of the gear housing are obtained by solving a system of Lagrange differential equations of the second kind. The mathematical model of the considered mechanical system created for this purpose takes into account the elastic nature of the casing attachment to the traction motor. The values of the frequencies of the natural vibrations of the gear housing obtained make it possible to evaluate its dynamic loading at the frequencies close to the resonant ones.

The problem of the assessment of the continuous welded rail track stability at its thermal elongation is considered in this paper. The method for determining the stress-strain state of various elastic objects developed by the specialists of JSC “VNIKTI” is analyzed on the example of a rail of a continuous-welded track section. The essence of the method is to determine the dependence of the natural frequencies of rail vibrations on the applied longitudinal force. As a means of obtaining such a dependence, a modal analysis of a track section model carried out using the finite element method was chosen. The methodology for calculating the natural frequencies of rail vibrations and the description of the created model of the track section and its properties are presented in the paper, the contact interactions of the model elements and boundary conditions are defined in it. Calculations for determining the natural frequencies and modes of rail vibrations are performed, the first four modes of rail vibrations obtained by calculation and experimental methods are shown. The assessment of the adequacy of the created model of the track section is carried out by comparing the natural frequencies and modes of rail vibrations obtained by calculation, by modal analysis methods and experimentally when measuring vibrations on a full-scale object - assembled rails and sleepers, having a similar design compared with the model. It was decided to use the distance between the vibration nodes as a criterion for comparing the obtained modes of natural rail vibrations. The first mode of vibration is selected for further studies. Calculations were carried out and the dependence of the natural frequency of the first vibration mode of the rail on the longitudinal force applied to it was obtained using the created model of the track section. The obtained dependence can be used in the method proposed by the specialists of JSC “VNIKTI” in order to determine longitudinal force, applied to the rails on the full-scale section of the continuous welded rail track.

In this article, the problem of assessing the stability of a continuous welded rail track during its thermal elongation is considered. The article considers the method of determining a stress-strain state of continuous welded rails proposed by specialists of JSC “VNIKTI”, which is based on the use of the dependence of natural frequencies of rail vibrations on the applied longitudinal force. Such a dependence can be obtained with the help of the calculation method using a finite element model of a track section. The reliability of such a dependence can be assessed by comparing the results obtained using the calculation method with the actual values of natural frequencies of rail vibrations, depending on the longitudinal tensile and compression force applied to a full-scale facility. The track panel is chosen as such a facility. In order to obtain the actual dependence of natural frequencies of rail vibrations on the applied longitudinal force, a specialized test bench is developed. The development of the test bench included designing the test bench elements and creating finite element models of main load-bearing elements of the test bench - a stop, support and traction, as well as their subsequent strength calculation to confirm the operability of the selected design under necessary loading conditions. The strength is assessed using the safety factor for the yield strength. Calculations using the finite element method have shown that the test bench design has sufficient strength. The developed test bench will allow performing tests for the purpose of the verification obtained using the calculation method of the dependence of rail vibration frequencies on the longitudinal tension and compression force applied to it, as well as for testing the proposed method to assess the rail longitudinal force during its thermal expansion.