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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.

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 analyzes the influence of parameters and operating modes of traction power supply system on the value of the useful energy recovery and the amount of electricity losses caused by the energy recovery through the traction power system to various consumers. The amount of energy lost in recuperation determines the degree of efficiency of its use. The approaches to the sequential determination of the recuperation energy efficiency and the calculation of the numerical values of the quantities characterizing the parameters of the traction power supply system, which are necessary for an adequate analysis of the energy distribution flow distribution, are proposed. It is determined that it is sufficient to use the regression analysis method to estimate the influence of the parameters and operating conditions of the traction power system on the energy efficiency of the recovery. The values of the relative resistance of the contact network are calculated depending on the type of the contact suspension, as well as on the traction network supply circuits. It is shown that the parameters and operating modes of traction power supply system affect the losses in the contact network, the losses in rectifier-inverter converters and traction transformers of direct current traction substations, the amount of energy recovery from tires of traction substations, as well as the relative change in losses in the system traction power supply with the use of regenerative braking.

The article discusses a problem of the efficiency of the regenerative braking’s increase on the DC railway section. For the detection of the causes of the decrease of the specific regeneration’s level on the area an algorithm is offered, which enables to determine the causes of the decrease of the specific regeneration’s level on the arbitrary monitoring’s area in view of the determination of the locomotive’s capacity for work, work parameters of the electric traction system and the executed graphic time-table. In the article the main phases of the algorithm’s work were considered by the example of the one of the railway sections.

The article outlines methodological approaches to assessing the effectiveness of measures aimed at improving the efficiency of recuperative braking application and the use of energy recovery. An example of calculating the energy efficiency of recuperation on a double-track section of direct current is given. The analysis of the influence of changes in such parameters of the section as technical and district speed of freight trains on the efficiency of energy recovery. The article presents the results of estimating the energy recovery components that form the economic efficiency of recuperation, and describes the approaches to predicting the change in this efficiency, depending on the change in the influencing factors.

The problem of increasing energy saving when using fuel in heating furnaces of forging and thermal shops for heat treatment of metal under pressure treatment (forging and stamping) and heat treatment (quenching, tempering, carburizing and nitrocarburizing) is considered. Ways to improve energy saving in industrial furnaces and issues of reducing fuel consumption in thermal processes were studied. The problem of rationalizing the regeneration of low-grade heat of flue gases was not solved fully enough, since economic factors and the influence of the determining parameters on the temperature and thermal regimes of heat recovery plants were not fully taken into account. Thus, it is relevant to address the issue of the appropriate degree of recovery of the thermal potential of the gases leaving the heating furnace, finding the most favorable parameters of heat recovery plants. A criterion is proposed for assessing the effective level of the degree of utilization of the heat of exhaust gases at the outlet from the heating furnaces. It is proposed to evaluate the efficiency of the heat recovery plant and determine the optimal degree of heat recovery from flue gases leaving the heating furnace based on the difference in the changing costs for the construction and operation of the heat recovery plant. A method and an algorithm for determining the technically and economically feasible degree of utilization of low-potential heat of fuel combustion products after furnace units in a heat recovery unit have been developed. The developed algorithm provided the necessary optimality conditions, was checked for sufficiency by conducting studies on the existence of an extremum at the test point and the positivity of subsequent derivatives. The dependences of the economically viable temperature of the fuel combustion products after the heat recovery plant on the determining factors, basic values, price indicators and initial data are obtained, which, in the case of reconstruction and modernization of the furnace facilities of forge and thermal shops, minimize the costs of reconstruction and increase the efficiency of its use. The practical significance of the application of the proposed developments for practical use in the design, reconstruction and modernization of the furnace facilities of forging and thermal shops has been substantiated.

The article is devoted to the issue of power loss measurement in DC traction networks. The purpose of the work is to define the indicators characterizing the degree of determining the energy loss values accuracy when using the method of restoration of the train situation. In the article the analysis of methodical error the value arising at measurement of power losses in a traction DC network is conducted. The occurrence of the error is caused by the indirect measurement method, which is based on the principle of synthesis of instantaneous circuits in real time. The synthesis is based on direct measurements of currents and voltages on the busbars of adjacent feeding and switching points, for example, a traction substation and a sectionalizing station. The data obtained are processed in accordance with the algorithms adopted in the article, as a result of which the coordinates of loads and their current consumption are calculated. In the process of synthesizing instantaneous circuits, it is possible that such a train situation may occur, which will lead to the emergence of a methodical measurement error, due to the peculiarities of the logical and mathematical apparatus of the train situation recovery method. In this paper, has been performed a probabilistic analysis of the possibility of occurrence of methodological error when several traction loads will be present simultaneously on the measuring section, that is, the dependence of the occurrence of the measure of uncertainty on the daily size of train traffic and the dependence of the occurrence of the measure of uncertainty on the minimum inter-train interval. As a result of the study, the proposed method application the limits were established by energy loss measurement the permissible error the criterion. The methodological error the value of the measurement at different variants method of movement on the railroad studied section was assessed

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 results of mathematical modeling of the optimization of maintenance cable lines are presented in article. The results can be used to calculate the optimal frequency and number of major repairs and substitutions of cable lines.