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Method of installation places and power choice of reactive power compensation devises in traction power supply system in condition of increase freight miles are introduced in this article. Approaches to definition of reactive power optimal criteria with reactive power compensation installation are denoted. Three criteria for estimation of reactive power compensation installation are offer to review. There is provided method of optimality assessment of this choice.

The paper considers a traction power supply system with a voltage of 27,5 kV AC. In the MATLAB-Simulink software environment, a calculation model has been developed that takes into account the parameters of the external power supply system, the train schedule and the current consumption of the electric traction load in the inter-substation zone. It is shown that when choosing the power of the compensating device according to the average value of the reactive power consumed by one train, its passage through the inter-substation zone with direct current causes the same average power losses in the wires of the catenary as in the absence of a compensating device. An increase in the number of trains simultaneously located in the inter-substation zone with the same power of the compensating device entails a decrease in power losses in the wires of the catenary relative to a similar situation without a compensating device, however, the reactive power is only partially compensated. In the calculations of compensating devices, it is proposed to take into account the real existing train schedule, based on the probabilistic assessment of which the average daily reactive power consumed by the electric rolling stock is determined. In this case, it is necessary to take into account the power losses in the catenary. The use of unregulated compensating devices is advisable in areas with a constantly present load. When choosing step devices for transverse capacitive compensation, it is proposed to calculate their power based on a probabilistic analysis of the train traffic schedule and current consumption in the inter-substation zone. When the probability of the appearance of a certain number of trains exceeding 50%, the most effective are compensating devices, the power of which is selected on the basis of the average power consumption of all trains without taking into account the time of no load in the inter-substation zone, as well as two-stage devices, the power of the first stage of which is selected according to the current consumption of the two most likely occurrences of the number of trains.

With the purpose of providing capacity on the West-Siberian railway, in recent times, adjustable reactive power compensation devices have been introduced. The schematic construction and parameters of such devices on the market are significantly different. In connection with this, it is necessary to choose from the set of schemes the most effective, corresponding to specific technical and economic conditions. The article assesses the power losses in the main equipment of two devices from different manufacturers, namely static thyristor compensators of reactive power produced by "KER Holding" Kazan and "Aidis groups" Moscow, installed on the Alambay and Novaya Dubrava sectional posts of the West Siberian Iron roads. The power losses in the equipment are calculated taking into account additional losses from the influence of higher harmonic components. The analysis of the circuit design of both devices in terms of loss reduction is carried out. Dependences of power losses in their elements on the generated reactive power and the current of the thyristor-reactor group are constructed. Probabilistic functions of the distribution of the current of the titrator-reactor groups of devices are given at preset settings. The results of measurements of power consumption of devices for own needs are presented. The effect of reducing power losses in the traction network from switching devices with losses in their main equipment is compared. On the basis of the work done, the elements with the greatest losses are identified. The features of each device, affecting the power loss in the main equipment, are described. Conclusions are drawn about the effectiveness of the schemes under consideration. Methods for reducing power losses in basic equipment and consumption for energy consumption are proposed.

Global investment projects of JSC "Russian Railways" to increase turnover suggest an increase in the load on the existing areas of electrified railways, in connection with what is urgent problem of passing the required number of pairs of trains at railway stations. Electricity consumption in railways AC characterized by a rather high consumption of reactive power due to the specifics of electric rolling alternating current, which leads to increased levels of stress and loss of power and, consequently, reduce the energy efficiency and the potential capacity and carrying capacity of the railways. One of the least capital-intensive, and in some cases the only possible rational way to strengthen the system of traction power supply AC is the use of transverse devices for reactive power compensation. The article describes the method of determining the power and choice of accommodations in the area of ​​the railway regulated and unregulated devices transverse reactive power compensation systems, traction power supply 25 kV and 2 × 25 kV. The calculation of the input impedance of the external inductance and traction power supply, the main options for power supply circuits and sectioning traction network devices and placing transverse compensation of reactive power, check to ensure a minimum level of voltage at the pantograph of electric rolling stock. The results can be used as the design of new railway sections, and in dealing with increasing the capacity of sites in operation.

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.

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 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 paper discusses the main limiting factors limiting the volume of transportation of high-volume freight trains. Designated approaches to solving the problems presented by the use of compensating devices. The paper presents the method of selecting installation sites and the power of compensating devices in the traction network, taking into account the growth in traffic volumes, allowing to evaluate the positive effect of the installation of compensating devices on the prospect of increasing traffic volumes. Determination of perspective power consumption is proposed to carry out using power consumption forecasting. To assess the effect of the installation of compensating devices in the traction network, three criteria have been proposed: unloading traction transformers, increasing the voltage level at the consumer, and unloading the power transmission lines.