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He method of researching the dynamic properties of the railway crew in the action on it harmonic parametric perturbation, caused by the changing rigidity of the base of the rail, is set out. For such differential equations there are no regular methods of solving them, moreover, their exact solutions are not known at present, so they are used by approaching methods. A two-degree mechanical system with a harmonic parametric perturbation described by a system of ordinary homogeneous differential equations is considered. One of the hard-bone parameters is a function of time and varies from 2000 to 3000 N/m. To calculate the boundaries of dynamic instability (parametric resonance) a method of generalized Hill definers is used, which does not require the introduction of small parameters. The area of interaction of parametrically excited and forced vibrations has been determined.

The subject of the research is the power thyristor converter of AC electric locomotives and its influence on the power factor of the locomotive. A new method for increasing the power factor of AC electric locomotives with thyristors power converters is proposed and analyzed. These electric locomotives include locomotives of the 2ES5K, VL85, EP1 series, etc. At the initial of the paper, the existing methods of increasing the power factor are briefly considered and their disadvantage in comparison with the proposed method is indicated. The drawback of existing converters is also analyzed, which consists in the presence of a thyristor opening delay at the beginning of the supply voltage half-cycle. The proposed method implies the modernization of the control circuits of the thyristors of the converter, due to which, at the beginning of the half-period, a control current is spontaneously created on the control electrode by means of the supply voltage. As a result, the thyristors open with a minimum delay after the start of the half-cycle. To verification the effectiveness of the proposed solutions, a computer simulation of the operation of the power circuit of an electric locomotive in the ORCAD program was carried out. Simulation was carried out for two options: a power circuit with standard converters and a power circuit with converters upgraded in accordance with the proposed method. During the simulation, the change in the value of the power factor of an electric locomotive was investigated at different currents of traction motors, zone and angle of regulation. Analysis of the oscillograms of converter various arms currents the revealed that when using the modernized converters, the moment of the end of the network switching occurs earlier than in the standard circuit. There is also no area with negative voltage at the output of the converter at the beginning of the half-cycle. At the end of the paper, the values of the electric locomotive power factor are given under various conditions. These results show that the use of the proposed method increases the power factor of an electric locomotive by an average of 1.2 percentage points.

This article describes the standard field reduction system of traction electric motors of a contactor-resistors type using inductive shunts, its drawbacks are revealed. An improved field reduction system of traction electric motors of an AC locomotive based on IGBT transistors has been developed and proposed. The proposed solution will allow to exclude the copper-containing inductive shunt from the power circuit, while providing reliable protection in non-stationary operating modes of the electric locomotive, as well as reduce electricity consumption for train traction. To prove the advantages of the proposed the field reduction system of traction electric motors, a method of comparative analysis of electromagnetic processes of the mathematical model of the standard and proposed systems of the field reduction of traction electric motors of an electric locomotive obtained in the MatLab Simulink environment was applied. As a result, it is proved that the implementation of the field reduction systems of traction electric motors using IGBT transistors with the developed control algorithm provides an increase in the power factor of an electric locomotive on average by at least 4%, and also significantly reduces the ripple current of the traction electric motor.

It is shown that dynamic systems, «rolling stock - way» due to the unevenness of the path on length should be described by ordinary differential equations with variable coefficients, the method of analyzing differential equations with constant, variable and random coefficients describing the movement of electric locomotive nodes when they move along an uneven path. In the transition to a new paradigm, we can talk about areas of dynamic instability, which in the case of simple parametric resonances develop near critical frequencies, but this is not one specific point, but a zone that expands with increasing coefficients of parametric excitation. In addition, the presence of friction in the system does not guarantee the limitation of resonant amplitudes. The effect of parametric arousal factors on the width of the dynamic instability zone has been established. There are many other features in the behavior of differential equations with variable coefficients, so it is impossible to replace the action of unevenness with some equivalent geometric irregularity, since at this moment there is no exact solution to the problem with which to compare the results of approximate mathematical models.

The article considers phenomenological and modelling approach to researching of interaction of a deformable wheel and a plane of support, their advantages and disadvantages are mentioned. In the context of phenomenological approach the five methods of locomotive tangent tractive force calculation were considered. There certainly must be pseudo-creeping to let locomotive tangent tractive force do work and change the kinetic energy of a train in the point of wheel and rail contact. Locomotive tractive force experts calculate the power as product of the locomotive tangent tractive force and the velocity of translational motion of a train, although in fact the velocity of the point of force application must be assumed. It is applied to a wheel pair, then the velocity of this point must be used to calculate the locomotive power. According to this fact the locomotive power is found several tens of times reduced.

Based on the analysis of the empty rolling stock on the Krasnoyarsk and East Siberian Railways, the technical parameters that have a significant impact on the unloading of the wheel of the first wheel pair in the course of movement are determined. The design features of wagons influencing the safety coefficient of train traffic are considered. Statistical processing of these gatherings, according to the materials of official investigations, revealed a number of interesting features. One of them is non-normalized total gaps in the sliders along the diagonals of the wagons. This fact in the movement of empty car causes misalignment of the body, which in turn leads to a redistribution of the loads acting on the spring kits on the sides of carts and wagons. The influence of elastic suspension parameters (height, spring break) on the redistribution of loads acting on the sides of the trolley is considered. The misalignment of the body of empty wagons, especially wagons with a sufficiently small mass of unsprung parts and a high center of gravity, leads to a significant reduction in the safety factor. The calculation of the transverse guiding forces acting at the point of contact of the wheel and rail, as well as their effect on the unloading of the wheel. It is revealed that the body skew leads to a significant increase in lateral force, which affects the stability of the empty rolling stock.

In article it is made a calculation contact pressing taking into account change of aerodynamic carrying power depending on climatic conditions (in one and a two-phase stream), and as at change of working height of a current collector. Comparison of the received results with experimental data is executed.

Formed research methodology of assessing the impact of pulsed exposure with the one-hundred-Rhone joints of rails on the performance of the dynamic characteristics of the train crew. The dependence of the coefficient of the effect of pulse repetition on the level of energy dissipation in the system and the speed of the crew.

The technical condition of the cylinder-piston group has significant effect on the reliable operation of the diesel locomotive engines. The most susceptible to the premature failure is the head of cylinders. It is caused by the heat release rate of the combustion chamber detail. The increase of the diesel locomotive engines cylinder heads durability in operation causes the relevance of the researches. In the article the set of the factors influencing on the diesel locomotive engine cylinder heads durability is defined, their main groups and subgroups are found. In the offered classification the subjective factors which directly depend on the human activity are dominated. It is possible to reduce the influence of the subjective factors by means of the human activity wrong solutions reduction while operating and repairing locomotives. The measures that improve diesel locomotive engine operation and positively affect the reliability of the cylinder heads are considered. Simple in implementation methods to extend the service life of the cylinder-piston group are offered. They are decreasing temperatures gradient during the post-stopping period of the power point and upgrading cooling system.

In general, improvement of methods for electrical calculations aimed at increasing the accuracy of the results. One of the ways to improve the methods of calculation is the account in the calculation of the various factors that affect the accuracy of calculation of the traction power system parameters. This article describes an approach aimed at improving the method of calculation in the electrical part to improve the accuracy by changing the algorithm for calculating and accounting for a number of additional factors.

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.

The paper presents a calculation of the magnetic field over the cable with damage. The cable with damage is replaced to equivalent circuit «conductor - shield». The conductor and the shield is considered as two single-wire lines, loaded on the characteristic impedance to avoid reflections. For this equivalent circuit defined sine wave signal change in the conductor and the cable shield. These results indicate that in cable fault location conductor current is significantly changed and shield current reaches the maximum value. The values of the shielding factor is determined at dif-ferent frequencies for the continuous tubular aluminum conductor and steel spiral conductor. The magnetic field is determined on the earth surface over the cable with metal shield having a «con-ductor - shield» damage taking into account the shielding factor. The results show that the module and phase of magnetic field is incremented in the cable fault location, which can be fixed on the earth surface. The results of calculation will improve the methods and hardware for cable fault lo-cation searching.

The article discusses the criteria used to calculate the probability of failures of devices of the current collection system due to ice and frost deposits on a catenary. The purpose of the work is to determine the influence of climatic and operational factors (including the number of vibrating pantographs, pneumatic drums on electric locomotives within the boundaries of the Directorate for power supply and devices for mechanical cleaning of ice at power supply distances) on the probability of the occurrence of failures of the current collection system and their severity, which will allow to increase the reliability of operation of traction power supply devices in conditions of ice formation and the efficiency of investments by Transenergo and the Traction Directorate for the purchase of these funds. To determine the likelihood of failures of current collection devices due to the formation of ice on the wires of the contact network, it is proposed to divide all factors into climatic and operational. The choice of factors in predicting failures was carried out using a probabilistic Bayesian network based on statistical methods of data processing, as well as correlation and regression analysis. As a result of the research, the factors influencing the likelihood of failures of current collection devices have been determined, and their significance has been assessed using the calculated variances. A method is given for calculating the probability of failure for a conditional distance of power supply, which makes it possible to assess the adequacy of the equipment of Transenergo and Traction Directorates with devices for mechanical cleaning of ice from a contact wire, vibropantographs and pneumatic drums.

The known approaches to the classification of factors affecting the energy consumption of the train are considered, and their main disadvantages are identified. The validity of existing classification methods and the completeness of accounting for factors affecting energy consumption are evaluated. It is shown that none of the known approaches to classification gives a complete picture of all the influencing factors and the degree of their influence on the energy consumption of the train, since it does not fully take into account the physical nature of the individual components and the overall power consumption for traction. Based on the analysis of the energy balance of the train articulated principles and criteria for the classification of factors influencing energy consumption, considers the interconversion of different forms of energy and describe their energy diagrams in the different modes of the train movement. The analysis made it possible to identify the factors that affect the power consumption of the train in all modes of movement, and evaluate them according to various criteria. A classification of factors affecting the train's electricity consumption is proposed, which allows us to justify the correct method of accounting for each factor, develop measures to reduce the influence of individual factors on energy consumption, improve the system of analysis, rationing and forecasting of electricity consumption for train traction, and competently solve other problems of electric traction energy.

The purpose of this article is to analyze the voltage drop in the contact network caused by poor-quality operation of an alternating current electric locomotive when passing heavy trains. Heavy-haul traffic is considered today as a valid and necessary tool for increasing weight norms and increasing the throughput of railway sections. The article provides statistics on the passage of heavy and connected trains on the Krasnoyarsk railway for 2019 and 2020. For the effective use of heavy traffic, it is necessary to solve a number of problems, one of which is to reduce the voltage in the overhead network when passing heavy trains, this negatively affects the speed of the train along the haul, the conditions for cooling the power equipment of the electric locomotive deteriorate, etc. As a result of the analysis of the operation of the thyristor rectifier-inverter converter, a number of disadvantages were revealed. The reason for the low power factor of the electric locomotive lies in the use of an outdated element base based on thyristors, their closure is carried out only in the next voltage half-cycle, long-term switching and a large opening angle of thyristors leads to a significant reactive current in the contact network. Based on the analysis the voltage losses at the current collector, it was concluded that it is necessary to reduce the duration of the switching process of the arms of the rectifier-inverter converter, in which a short circuit occurs in the secondary winding of the traction transformer. An alternative version of the converter based on fully controlled semiconductor devices - IGBT transistors is proposed. The ability to open and close at any time of such elements allows you to minimize the phase angle and increase the power factor. Due to the almost instantaneous switching of transistors, the distortion in the contact network is minimized.

In article from positions of uniform life cycle locomotives, from creation before write-off, the major factors influencing the level of their reliability are considered. Value of these factors will give the chance to connect mathematical model the potential level of reliability put in the specification on design of new locomotives with the actual reliability in specific conditions of operation and on this basis to determine the optimum parameters systems of maintenance and repair corresponding to maximum efficiency of use locomotives for all life cycle.

The article describes a method for controlling electrical loads rail consumers using energy storage. Different types of energy storage devices used in rail transport were considered. Performed the optimization problem formulation, selected criteria and the method for its solution. As an optimization method used the method of Hooke-Jeeves. A method is proposed to determine the optimal parameters and the optimal control law of charging and discharging of the energy storage. The criteria and calculation expressions that can be used in the design and feasibility study of the effectiveness of implementation of the stationary energy storage for managing schedules loads rail consumers. The mathematical expression was proposed for the energy storage capacity determination. Two criteria were considered in the optimization problem: a minimum active power losses and minimum reduced costs, and a comparison of results. The form factor used to evaluate the changes in electrical loads. Control of reactive power in the AC mains can realize using semiconductor converters and an energy storage. As a variant the electrochemical cells (lithium-titanate batteries) could be used as energy storage for rail electric consumers. As a result, optimal control of electrical loads allows to get technical and economic effects.

Evaluation of fatigue life is based on the use of basic fatigue curves. However, due to large va-riety of possible design solutions basic fatigue curves cannot be calculated for all cases. In addi-tion, the production practice has a significant influence on the durability of structural elements. To predict the fatigue durability using the traditional method we need to consider the influence of structural and technological factors by introducing the correction coefficients established on the basis of the experience and accumulated experimental data. The correction coefficients are widely used in calculating the resource elements by domestic and foreign construction firms. Using the traditional method the match of the projected longevity and durability resulted in a bench test struc-tures are not always satisfactory. Often by conducting rapid analysis the sufficient fatigue curves absent, the closest in characteristics among the available are selected. The article presents the im-proved technique of numerical fatigue life prediction of structural elements by using the modified fatigue curves, considering the impact of structural and technological features of the products of the actual design. The results of calculated estimate of the resistance of fatigue thin-walled struc-tures and their comparison with experimental data are presented. On the basis of the work carried out was drawn the conclusion that by using the method of calculation of fatigue longevity using modified fatigue curves , considering the structural features fragments of products, the convergence of the results of predicting fatigue life and test bench results obtained higher than by using tradi-tional techniques.

The necessity of searching for new methods to improve the dynamic rationalized properties of the traction drive, which does not create contradictions between the conclusions based on the results of numerical parametric analysis and the results of the analysis of nonparametric factors, is established. A modified base point method is proposed that takes into account the possible presence of areas of conservatism of a rational parameter and provides for a procedure for checking for conservatism. The search results using this method for a rational version of a traction drive with a support-frame suspension of an electric motor and a gear reducer coincide with the empirical choice of different manufacturers of locomotives.

In the paper the device for reactive power compensation for the electric locomotives based on passive adjustable compensator was described. This configuration of the compensator improve the power factor of the electric locomotive in all operational modes and raise value of the power factor to its maximum possible value. The management of the compensator unit is based on the extremum seeking control autonomous voltage inverter. Mathematical modeling of electric locomotive showed increase the power factor to a value of 0,98.

The authors propose a model of justification of the duration of the operation liner-tamping-straightening and construction machinery. Using this model, we can evaluate the efficiency and reliability of machines on any object. This allows you to most reliably predict the timing of production of certain types of works and their cost at the design stage. The article presents the indicators of full-scale tests and the estimation of reliability of manufacturing operations. One of the main factors of reliability of work of construction machines is the utilization of their time. All normative documents are obsolete data on the utilization of machines during the working time, which need updating, as the machines are constantly improving. To assess the reliability of working machines, the authors developed a database of the results of field tests liner-tamping-straightening machines, cranes, excavators, bulldozers, pipe layers, drilling rigs and dredges. To prove the validity of database values according to the results of full-scale tests were carried out two stages of verification: logical and mathematical. After sampling in accordance with GOST R 8.736-2011 was verified that it belongs to the law of normal distribution using the criterion of Pearson agreement. It was further calculated the reliability and risk of the planned volume of work in scheduled period of time. When it was considered the utilization ratio of machines time and the risk of deviation from the mean. The proposed approach to the assessment of duration of liner-tamping-straightening and construction machinery can be extended to any type of equipment and will allow to obtain numerical values for evaluating the reliability of production work in the scheduled time, which is very important in the construction, repair and maintenance.

The article considers one of the ways of improving the energy efficiency of AC electrical system railways 25 kV, 50 Hz. The proposed approach allows to determine the optimal location and capacity of an unregulated device for compensation reactive power according to the criterion of minimum active power losses in a traction electrical system. Modeling of trains on the site was made using instant schemes. Description of the traction power supply system implemented by the node potential method and Steinmetz’s symbolic method. Optimal value of reactive power for all possible locations of a compensating device was calculated numerically by an optimization method of Hooke-Jeeves according to the criterion of minimum active power losses in the traction network. The mathematical model allows to consider the elements of the traction network, schedules of trains, change of traction loads of electric locomotives, schemes of overhead network. The proposed approach was considered on the example test problem, which solution allowed to determinate the optimal location and required value of reactive power of an technical device. The placement of a compensating device in a certain place will allows to minimize the power loss in the contact network, track circuit and traction transformers from the flow of the reactive component of the current in average for all instant schemes with various traction loads. An unregulated technical device for compensating reactive power which is located between two traction substations reduces energy consumption for traction of trains on the 1 - 2 %.

In the context of the objectives of and compliance with transportation of corridors for rolling stock and improving the technology of transportation of different modes of transport considered minimization of the geometric factor in positioning navigation, peculiarities of determination of errors of coordinate of the moving objects along physically fixed trajectories on the plane, it is proved the statement about the possibility of recovery of the trajectory of the mobile point on the plane with continuous or discrete measurements of one coordinate.

The article deals with the issues of joint use of a low-temperature solar collector and a heat pump in a solar heating system, the combination of which allows for high energy efficiency and stable operation of the system for the entire period of the year. The study and development of innovative technologies in alternative energy is a topical issue of today. Based on the actual statistical climatic data of the city of Omsk, a thermal calculation of the solar collector and the air heat pump in the heat supply system of the building was made. The values of solar insolation and the angle of inclination for the city of Omsk by months determined depending on latitude are given, the dependence of the change in solar insolation of the city of Omsk on the period of the year is plotted. The proposed scheme allows creating high energy efficiency and stable operation of the system during the summer and transitional months of the year. A method for calculating the generation of thermal energy using a combined system is given. The required number of tubes of solar vacuum tubular collector SVK-20A has been calculated. The work of an air heat pump and a solar collector according to a bivalent scheme is proposed, and a graph of the heat load of the heating system is also considered. The thermophysical properties of the working substance of a solar collector and an air heat pump are studied with a change in ambient temperature, the dependence of the freezing point of aqueous solutions of ethylene glycol and propylene glycol on the mass concentration of glycol is studied. A technical calculation of the COP coefficient for one of the educational buildings of OSTU was made. An effective option for using this system is proposed - heating systems «warm floor», «warm walls» or «warm ceiling».

In research consider a methodology the remaining life assessment of rail with fatigue crack in lower flange. Obtain the stress intensity factor equations for crack size and kind of stress: bending stress, thermal and residual stress. Make up an fatigue strength analysis of rail P65 and under different conditions of loading and remaining life calculation of damaged rail when given conditions of loading. Submit a assessment evaluation rail reinforcement in cyclic crack growth rate.