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The article contains methodology for assigning losses in two-element frequency converter (in rectifier and dc-ac converter). which allow to replenish mathematical model of back to back rig test method for induction motors and to use it in design induction motor rig test, also for calculation electrical power test rig which consumed from electrical network. Practical value of the methodology is no need in using electrical measurement instrument for ac-dc power with frequency different from 50 Gz.

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.

Each of the proposed circuits is composed of inverters. These devices are sources of non-sinusoidal voltage, whose frequency can vary within a wide load range of the test engine. Therefore, to measure the power in such conditions requires either the use of special complex of hardware-software complexes to perform the direct measurement or the development of indirect methods for determining capacity. Such methods proposed for each of the schemes. The essence of the developed methods consists in a preliminary experimental determination of the dependency of the losses in the rectifiers and rectifier-inverters circuits from the power supplied to him. These dependencies are further processed during the test, using only the General-industrial electric meters that measure power consumed by the frequency Converter, and the power consumed (generated) asynchronous motors is determined by the indirect (calculated) by. On the other hand, pre-experimentally received dependence of losses in frequency converters from power consumption trolled (generated) asynchronous motor energy, you can calculate the power consumed by the frequency Converter from the network in a wide range of loads that can be used in the design of testing stations for asynchronous traction motors.

This article presents the results of changes calculations in the energy efficiency indicators of the Moscow Central Ring, such as the specific consumption of electricity released for traction by trains of traction substation meters, specific recovery, technical losses of electricity in the traction power supply system when it is transferred to electric rolling stock, including technical recuperation energy loss, depending on various installation options of rectifier-inverter converters in traction substations part.

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 considers the current situation regarding the organization of control over the use of traction and energy resources of JSC «Russian Railways». The main provisions of the proposed method are stated. The influence factors on the specific electric power consumption of electric locomotives of series 2ES6 and VL10, as well as the evaluation of the quality of the constructed models of multiple nonlinear regression were estimated. New scientifically grounded technological solutions and developments are proposed that allow to reduce the specific consumption and unproductive losses of electric energy within the boundaries of the railway accounting areas.

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 .

In article the issues of electric power imbalance in train traction research are considered, including the method providing an estimation of the contribution of imbalance components to its total value with the possibility of their separation between the participants of the transportation process: the electrification and power supply service, the automatics and telemechanics service, the directorates of locomotive traction and motorized rolling stock. Described method allows in more detail to analyze the factors that affected the change in the components of imbalance and further develop organizational and technical measures to reduce it.

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 discusses the assessment of the impact of train schedule on the amount of electricity consumption for traction on sections of DC I-th profile type way. The proposed parameters of the train schedule, influencing the electricity consumption for traction on sections of DC I-th profile type way. The major scheduling options included statistical quantities and parameters characterizing the conditions of the batch passing trains, stop and solid thread schedules for truck-driving. Based on simulation modeling provided the main based on changes in the volume of electric energy for traction on the plot of the traction electric supply system when changing the parameters of the timetable. The dependences of the volume change of electrical energy for traction allow you to evaluate and determine the ranges of the parameters of the graph in which the variation of volume is minimal. in the considered ranges of the parameters of the train schedule, the amount of electricity for the areas of DC with the I-th profile type varies within 1 % with the constancy of other factors..

This article presents the rationale for the need to change the methodology for determining the absolute and relative values of energy losses to train traction. It is shown that when determining the relative value of the losses, it is necessary to take into account the amount of recovery energy returned to the contact network by electric rolling stock meters. To increase the accuracy of determining the absolute value of losses, it is necessary to take into account the energy consumption for the needs of the traction power supply system for prophylactic heating and smelting of ice on the wires of the contact network, as well as to ensure uninterrupted voltage on inactive electrified sections of railways. A formula is proposed for estimating the component of electric power losses in the contact network from the flow of energy recovery taking into account changes in the methodology for determining the loses of electric power for train traction.

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.

The article deals with measures to improve the energy efficiency of the transportation process. The necessity of creation of an automated system for monitoring the energy efficiency of the electric rolling stock. The algorithm, which allows to determine the reasons for non-locomotive crew specific rules of electricity on the trip. Developed form of protocols, reflecting the information on losses of electricity on the basis of a trip with the time and place of their origin.

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.

The paper deals with benefits of a new rectifier-inverter converter of an electric locomotive based on IGBT-transistors. Main directions of heavy haul traffic's development are considered for Siberia and Russian Far East electrified railways. Throughput and carrying capacity of power supply devices extremely depends on the voltage level in the catenary network of electrified sections of railways. Objects of our research are electric parameters of the 25 kV, 50 Hz AC traction power supply system. Operation parameters of two different types of the electric locomotive’s rectifier-inverter converters are calculated and discussed. We investigated operation parameters for thyristor-based and IGBT-transistors- based rectifier-inverter converter. Current and voltage curves for the thyristor and the transistor type of the rectifier-inverter converter are given and discussed. Similarity factor of current curves for electric locomotives was calculated by equivalent sinusoid’s .method. Quantitative assessment of the voltage level, currents and voltage losses in the AC catenary network is given. The graph-analytical method was used for constructing currents and voltages vector diagrams. It is proved that electric locomotives with a new rectifier-inverter conversion based on IGBT transistors provides a reducing of the total voltage losses in three times in the traction network comparing the thyristor conversion's operation.