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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 article presents the main results of experimental studies within the boundaries of the Fadino - Novoseletsk, Novoseletsk - Strela interstitial zones of the Entrance - Irtysh section. As a result of the research identified problems that currently hinder the online monitoring of operational parameters of the electric rolling stock (EPS) and power supply devices: a lack of data on the work of the traction substations, the presence of EPS without registration motion parameters (RAPS), the lack of process data collection with RAP, the lack of a single source and process for obtaining data, insufficient memory storage device of cartridge, lack of data latch on the locomotive in General, lack a set of fixed parameters, non-constant sampling of parameter fixing, insufficiently detailed final documentation, imperfect software for exporting data from cartridges and lack of binding to global time. Shown the possibility of joining data from different automated systems of JSC "RZD" and measuring systems OSTU, which will allow us to estimate the losses in the traction network, the expense on own needs of electric rolling stock , the electric power consumption for traction and return of electric energy to contact network, as well as move forward with implementation of predictive control operation modes of the electric rolling stock and power infrastructure and Railways in a changing environment in the transportation process, to ensure the best conditions for the realization of tractive effort, regenerative braking, set train schedules, including in case of critical restrictions on the part of the power supply system, preventing train traffic from stopping.

The article describes the types of irrational electric power losses for train traction and sets the annual planning levels of their improvement. Represented the basic methods of irrational electric power losses determination which are currently used in JSC "Russian Railways". Shown an example of the irrational losses determining algorithm in case of making up for train delay and given its description. Formulated technical results of the proposed method for determining the irrational electric power losses .

The article considers an approach that allows to reduce the asymmetry of consumed currents by traction substations of railways from a three-phase power supply system using a compensating device with an asymmetric structure installed at the substation. Reactive currents of the compensating device allow to redistribute between phases of the traction transformer active and reactive power of asymmetric traction load and to receive symmetric load of three-phase power supply system. The theorem is proposed to determine the conductivities and reactive currents of the branches of a compensating device with an asymmetric structure depending on the traction loads. The article presents the calculated expressions, which can be used to calculate the conductivity and reactive currents of the branches of the compensating device for any traction load of the feeders, in which the equivalent load, including the reactive currents of the branches of the device and the currents of the feeder zones will be symmetrical and active. As an example of the application of the theorem and the proposed expressions, a test problem is presented in which the secondary winding of a traction transformer with asymmetric traction load of feeders is considered, the conductivity of the branches of the device is calculated. With the use of vector diagrams shows the receipt of a symmetrical system of currents of the secondary winding of the traction transformer. Mathematical expressions allowing to realize the necessary law of regulation of reactive currents of the device are given. The necessary ranges control of reactive currents of the compensating device on traction substation on the set probabilistic laws of change of traction loadings are defined. Various options for the practical implementation of a compensating device that will provide the necessary inductive or capacitive current of each branch are considered.

The article considers one of the ways of improving the energy efficiency of three-phase power supply system of industrial and railway enterprises. Presented and proved a theorem, which allows to determine the necessary conductivity and the reactive branch currents compensating device with asymmetric structure, for which the equivalent conductivity of these elements and the load will be symmetrical and active. In three-phase electric circuit of an alternating sinusoidal current reactive elements allow to redistribute active and reactive power between the phases. The use of a compensating device with asymmetric structure will reduce losses from the occurrence of reactive currents, reverse currents and zero sequence in low-voltage three-phase power system. As an example of the use of the theorem and the calculated expressions for determination of conductance of the branches of the asymmetric compensating devices a special test problem was considered. It shows the values of power losses, the coefficients of voltage unbalance with and without using the device. Considered possible options for the practical implementation of such technical devices.

This article presents an algorithm and a method for calculating power flow of an open electric network with a voltage of 6-35 kV, taking into account the temperature dependence of active resistances. Calculation of the electric and thermal conditions of the electric network is carried out with a joint solution of the equations. The determination of stresses in the nodes is carried out using the inverse matrix of the nodal and intrinsic conductivities. The inverse matrix of nodal and intrinsic conductivities is determined based on the well-known direct Jordan-Gauss method. The equation of the heat balance of the wire used to calculate the actual temperature is solved numerically. Convective heat transfer is recorded only for forced convection, because wires of overhead power lines with a voltage of 6 kV and higher are located on various types of poles, at a height of at least 10 m. This fact allows us to abandon the use of formulas for natural convection and use expressions only for forced convection. Accounting for solar radiation in the presented algorithm is possible on the basis of two methods: simplified and considered in the standard of PJSC FGC UES, which allows you to take into account the actual location of the wire relative to the north. Using the test circuit as an example, the steady-state mode was calculated taking into account the temperature dependence of the active resistances. The results of a numerical experiment are presented, confirming the operability of the developed algorithm. The refinement in determining active power losses with and without taking into account the heating factor for the considered circuit is about 13%. Verification of the algorithm that implements the method of calculating the steady state (SS) of an open electrical network of a medium voltage class taking into account the temperature dependence of active resistances showed that in technically acceptable modes the developed algorithm has good accuracy in comparison with the RastrWin3 software package.

The article deals with the modeling of the electric rolling stock and traction power supply system with the aim of solving the problem of reducing the electric power consumption for the traction of trains in the conditions of changing the schedule of freight trains. Simulation modeling is performed for the conditions of changing the mass of the train and the load on the axis. The description of the results obtained is based on regression models, the order of application of models in practice is given.