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The article provides a solution to the system of equations for the voltages and currents of three single-wire lines with regard to their inductive and galvanic influence.

Theoretical analyze of liquid fuel movement in low-pressure line (LPL) of diesel fuel supply systems is implemented. To solve LPL the equations set of homogeneous blend is suggested. It is shown that when using alternative fuels in locomotive and ship diesels the retrimming of fuel equipment is required, and it’s reasonable to use the degree of irregularity of working process as diagnostic indicator.

The subject of the study is the fuel utilization system of a diesel power plant as a diesel locomo-tive or other vehicle main lead, which is a complex technical system consisting of actual diesel in-ternal combustion engine, fuel lines and low pressure fuel processing and high pressure line includ-ing various elements of liquid fuels consumption dosing and control. The aim of our study was to analyze the system functioning, to determine the dynamic proper-ties and the nature of changes in the internal parameters of the system as a whole. To achieve the goal the system analysis methods were used. The processes of complex technical system operation were interpreted by means of the continuous linear stationary deterministic model of the list of others. For this particular model the body of mathematics developed on the basis of linear differential equations with constant coefficients is the most complete one. The chosen mathematical model was presented by us in the first stage in the form of a finite graph as a subgraph of obtained earlier generalized model which had both methodological and theoretical foundation. In accordance with the methodology of the systematic approach the graph model of the diesel power plant fuel utilization system operation was described in relation to major significant factors affecting the system parameters transformation dynamics. Given the complexity of the of fuel ignition and combustion mechanism located in the diesel engine cylinder, the use of the techniques of the modern automated control theory is adopted for numerical processes simulation with the system described in terms of the said theory. The criteria of efficiency, mechanical loads and thermal loads levels were chosen as the fuel utilization system internal state variables. Taking into account the Pareto principle the most important efficiency criterion components were chosen for the analysis; and the system of differential equations of the efficiency dynamics in the form of three balance equations was created. The factual description of the included equations allowed us to derive preliminary qualitative conclusions about the dynamic properties of the internal criteria: controllability, observability and stability of the fuel utilization system. The differential equations system parameters linearizing procedure and the introduction of small deviations allowed us to obtain the dynamic mathematical model of the fuel and air transfor-mation in the diesel engine heat cylinder. As the result of transformations we have obtained the equations presented in the form of the matrices, which allowed us to conclude that the process of the fuel and air transformation in the cylinder is controllable, the system is asymptotically stable, and the process is stochastic with the presence of perturbing parameters influenced by the engine's variable modes of operation. The further research areas have been suggested, and the practical results have been predicted: the creation of optimal (in terms of efficiency) control system with the technical solution in the form of the optimal controller (in relation to fuel consumption).

Despite significant progress in the development of accounting systems, there is almost universal growth accounting losses of electricity and reduce its quality. Along with the introduction of modern energy efficient electrical problem efficiency of electric energy in the stationary energy sector can be achieved through the implementation of active-adaptive technologies for controlling the operation of compensating devices, controlled means of voltage control, switching and power equipment and diagnosis based on digital technology, including automatically maintain a minimum transmission losses when the load. Management of objects offered no traction electricity consumers based on adaptive technology and hardware-software optimization mode parameters in real time.

The article describes the general principles of the computational model of the traction power supply DC Railway to assess the potential energy recuperative braking, as well as ways of approbation the resulting model to determine its adequacy.

In the article suggests a changing the algorithm of the rectifier-inverter converter electric locomotive VL85. This will allow the individuallyto regulatevoltageon traction engines. In this case willpreserve a singlecentralized system ofcontrol of allelectricconverters. The proposed solutions may be used for liquidation started spinning of wheel locomotive. Tractive force the remaining wheelsets will not decrease.

The analysis of the influence of the organization of the formation of United freight trains on the throughput capacity of railway sections has been carried out. The results of electrical calculations of the 3.0 kV dc power supply system of 3 sections of the Sverdlovsk and South Ural railways are presented when controlling the speed of trains from 50 km / h to 100 km / h with various locomotives while passing two single and one connected cargo trains using the system of contactless automatic voltage regulation in the contact network, allowing to assess the throughput capacity of the three sections. In the course of the calculations, the developed refinement method was applied using the correction current factors KIxx and KIst. Proved the need for their use in electrical calculations.

There is a trouble that electrical energy of trains which have a recuperative braking uses partly for DC railway, because there are not different consumers of the electrical energy in this time. The method was offered, it allows to find optimal parameters of a stationary energy storage, which locates on a traction substation. This method can be used for designing and determination efficiency of an energy storage.

There is the way for increasing efficiency of recuperative braking, using an energy storage device on electrical locomotives of DC railway. This device must store a part of recuperative energy. In the article the approach was considered, which allows to find parameters of an energy storage device, this device must be placed on electrical locomotives of DC railway, a part of recuperative energy can be returned to electrical network.

The article shows that the replacement of concrete poles should be based on their actual corrosion state. Authors propose a new method for determining the corrosion state of the contact system concrete poles underground part, which allows to carry out measurements on the two poles at the same time. In this case, second pole acts as a current electrode. There is a formulas for determining the resistance of concrete, resistance and capacity of «steel - concrete» interface region. This algebraical expressions are results of the transient process analysis for the contact system poles equivalent circuit. The values of these parameters define the corrosion state pole in the underground part. Using of the proposed method will significantly reduce the time and labor costs of diagnostic procedures.

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.

The contact line is a special kind of power overhead line with multiple electrical connections of wires, which form a complex topology of the linear electrical circuit. Analytical models simplify the real topology of the contact line and it limits their functional application. It is possible to take into account the topology of contact line when using tools of computer simulation, but it entails complicating the computational algorithms of the model. The aim of this article is to determine the conditions for the application of current distribution models and the development prospects in this area. The article describes the existing models for calculating the current distribution in DC contact line: a model of natural current distribution, linear analytical models, model with an infinite number of droppers, a model with a direct application of Kirchhoff's circuit laws in matrix form, and a finite element model. The article contains the main provisions and calculation capabilities of each model. Contact line KS-250-3 acts as a calculation catenary for the comparison of current distribution models. You can use the results of the article to select the optimal design distribution model for the design of the contact line, thermal analysis, current-carrying capacity calculation, identification and elimination of «weak point».

The new method of parametrical identification of three winding transformer by using phase domain is proposed. Transformer model represents as lattice equivalent circuit.

The article describes themain types ofdamageinsulatorscontact network, presents statisticsfortheirfailures. Identified weaknessesin existing methodsof diagnosingsayabout the relevance ofthe problem, especially in the areasof railwaysDC. Made experimental investigationson the measurementof the electrostaticfield on theinsulator strings. Analysis of the studiesshowed that the presencein the string of faultyinsulatorsleadsto an increase inthe electrostatic fieldaround them. Proposed a technicaldevice noncontact measurementof electrostatic fieldandmethod of determining thefaultyinsulatorin the string.

As a result of tension increase and significantly loads on the overhead contact lines, there is need to research the tensile stress value for contact and messenger wires. In this paper, the author reviewed the wires operation conditions concerning the thermo-mechanical load. The author has analyzed the results of contact wires low-temperature creep tests. The real rate of contact wires creep is as appropriate as the standard values. At the same time, copper wire elongation is faster than bronze. The author has provided results about contact and messenger wires ultimate tensile stress tests, heated at different temperatures. The ultimate tensile stress rate for the copper and bronze contact wires is reducing by 9 % with temperatures increasing. The ultimate tensile stress rate for the cop-per messenger wires is reducing by 11 %, for the bronze wires - by 4 %, with rising temperatures to 150 °С. Test results have shown that heating of copper wires to temperatures above 90 °С and bronze wires to temperatures above 120 °С leads to a significant immediate reduction of strength. Working conditions for the overhead contact lines wires are close to the critical one. It is not sufficient for reliable and safe operation Author offers to modify regulatory requirements for contact and mes-senger wires concerning permissible heating and also not to divide short-term and long-term heat-ing and only to leave permissible heating.

The existing protection does not provide protective potential of traction substation grounding grid for the entire period of operation. This disadvantage is removed by improving of automatic drainage unit. The basis of the automatic drainage system is automatic control of drainage current by changing the pulse width of current. This method of current control allows the defined potential remain at the set value. The article presents a functional diagram describing the basic units of the improved automatic drainage unit. The results of the automatic drainage unit tests illustrate that the automatic drainage unit limits the current flowing through the grounding grid to the traction substation, allowing the potential remain at the set value Improved automatic drainage unit has great advantages in relation to existing and operated drain units at this moment and it can be recommended for introduction to the electrification infrastructure of the railway industry. Also this automatic drainage unit can be used for protection of other metal underground structures such as pipelines and other metal structures influenced by stray currents.

In the article the finite element model of the electrical contact pin wire - collector strip, which takes into account the complex interaction of electric and thermal processes. As the contact wire is selected worn MF-100, the current collection plate - two brands VJZ-metal and graphite. Microgeometry the body surface at the contact point is obtained based on the model of Greenwood - Williamson. It was considered the two extreme cases of possible contact between the contact wire to the plate. The results were analyzed and compared with the known experimental data. Calculated at what proportions contact force and contact current due to burnout occurs spark or arc. Identify ways to improve the model.

It is offered the technique for the assessment of the efficiency of the application of the mixed hydrocarbonic kinds of fuel in the power installations of diesel locomotives. The model calculations have been executed with a glance of the changing of the physicochemical and thermalphysic characteristics of the fuel mixtures and the service conditions of diesel locomotives.

The analyze of fuel supplying methods in diesels with respect of fuel properties was implemented. The new method was suggested, which can estimate impact of physical and energy fuel properties on power and economic indexes of a diesel. The diesel effective work conditions on low-viscosity fuels are formulated, including regulation and constructive changes in fuel supply system.

The article deals with the question of methodology stop imitation modeling when using modern instruments of mental resources, which are, for example, was Wednesday MatLab. In particular, analysis of factors that determine the duration of the simulation for a given level of accuracy desired results.

The purpose of this article is to create mathematical models for a comprehensive assessment of the quality of repairs of collector-brush assembly drive motor vehicles, including an assessment of mechanical and switching components. The objectives of this study are to determine the linguistic variables based on the generated set of diagnostic features, including "beating of the working surface of the collector", "RMS heights collector lamellae", "amplitude of the first harmonic component of the profile of the collector", "the amplitude of the second harmonic component of the profile of the collector" "RMS heights collector slat excluding the first and second harmonic components", "minimum value of the second derivative of the profile of the collector function", "standard deviation of the second derivative of the profile of the reservoir function," "effective value of the higher harmonic components of the collector profile features" that have the greatest diagnostic value and determination of their membership functions, as well as the definition of the complex index of quality of repair and its components: complex index of quality of machining and integrated commutation quality index in the collector-brush unit of the traction motor. Solution of tasks performed using the mathematical apparatus of fuzzy logic through the use of statistical processing of the results of these pilot studies and the calculation of the diagnostic value of the measured and calculated parameters. As a result of the research formed the mathematical model of quality repair in the space of selected features using the apparatus of fuzzy logic for calculating the value of the proposed integrated indicators for arbitrary values of diagnostic parameters. The results may be used to control the quality of repairs of collector-brush assembly of traction motors of the rolling stock.

A method to an assessment of influence on the expenditure of electrical energy for traction of trains, parameters of graphic time-table in the conditions of using the regenerative braking is being considered in the article. The retrieval of version with the minimal using of energy is based on the modeling of graphic time-table by different train-to-train intervals in the conditions of burst-mode access’ organization on the railway section. By results of modeling it is proposed to represent the derived dependence by changing of electrical energy’s expenditure on parameters of graphic time-table in the form of analytic function of several variables n-order forthe following using by normative plotting of movement for the purpose of curtailing electrical energy’s expenditure for traction on the trains.

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 analyzes the components of the energy efficiency of regenerative braking and the factors influencing the effectiveness of the use of regenerative braking and energy recovery. Methods of evaluating the energy efficiency of recovery and the results of experimental studies of the effectiveness of recovery. Achieved justification for the use of the method of simulation modeling as a method for evaluating the potential of regenerative braking. It shows the sequence of the work.

This article describes the features of the calculation of the unsteady wave processes in the system of traction electric supply. Mathematical model for calculation of wave processes at contact networks based on modified Laplace transform combined with using Fourier series. Practiced modeling of power supply system for identifying characteristics of wave processes in traction networks.