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The results of the pilot studies to increase the resource of the wheel of the rail stock are presented. The electroslag melting is used to restore the surface rolling and the wheel cam of the cars and locs wheels. The experimental research adopts its perspective.

In paper results researches of interacting of devices of a current collection of monorail transport are resulted. Negative aftereffects of a current collection are analyzed: acoustical noise, radio interferences and light irradiation at a sparking, deterioration of contact elements.

The article considers a suitability of mathematical model of stretched rod to determine the relationship of the parameters oscillations of the contact wires and their tension. This model allows you to determine the tension by the frequency oscillations of the contact wire obtained after the passage of the current collector. In this case, the speed of the electric rolling stock will not affect the frequency of the damped oscillations. Thanks to the proposed model, the labor intensity is reduced of determining the tension of wires without interruptions in the movement of trains is reduced and there is an opportunity of operational monitoring of the state of the contact suspension remotely.

A variant of application of a contact compensated chain suspension with levers and lateral current collection for a three-phase traction power supply system (TSTE) is considered. Two different-phase contact suspensions are located on different sides of the track axis. The electric rolling stock must have two current collectors that press on the contact wire from the track axis in opposite directions. The description of the design of the contact suspension as a whole and the main components, in particular, the fastening of the rods, which makes it possible to provide a vertical zigzag and limit the transverse movement of the contact wire, is made. At points at the supports, the levers are connected to the consoles and have a knot to create angular rigidity. In addition, the rotation of these levers is limited towards the axis of the path and in the opposite direction. This prevents the possibility of lashing of different-phase contact wires. In accordance with this design, a mathematical model of this contact suspension was developed based on the finite element method, which provides calculation in statics and dynamics, taking into account the current collector. To describe the pantograph, a common three-mass model is used. Based on the analysis of the results obtained using this model, the influence of the design parameters of the suspension, cross wind and the speed of the pantograph movement on the quality of the current collection is determined, the limits of applicability of the suspension under consideration, depending on the value of these parameters, are established. It has been determined that, in contrast to a conventional contact suspension with a vertical current collection, for suspensions with a lateral current collection, a side wind has a significant effect on the quality of the current collection. It is the wind speed that is the main factor limiting the possibility of using a suspension with lateral current collection.

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 article considers the processes of current collection in the system of AC electric traction in high-speed traffic. The existing devices of pantograph and catenary interacting by means of a sliding electrical contact are presented. The comparison of solutions with different horizontal geometry of the contact wire, which affects the speed of the lateral displacement of the contact wire at the catenary supports relative to the axis of the railway track, is given. It is shown that the speed at which the contact point moves along the pantograph strip is also important for assessing the wear of the sliding contact, as is the span length of the catenary supports, the curvature of the track and the speed of the train in the span limits. For the synthesis and analysis of the pair "pantograph strip - contact wire" with a sliding contact, a model for calculating the contact surface is obtained and the energy processes leading to wear of the components of the current collection system are considered. The results of modeling the interaction of the pantograph and the catenary with various variants of the zigzag arrangement of the contact wire are obtained. When implementing a technical solution in areas with high-speed traffic, the preferred method proposed in the article is the arrangement of the contact wire of a chain suspension with a zigzag period increased by two times compared to the traditional one. This solution provides a reduction in the speed of lateral displacement and increases the dynamic stability of the pantograph, reduces the cyclic load on the supporting and supporting structures of the catenary and increases the life of the contacting elements of the current collection system during high-speed traffic.

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.

The article describes how the inclination angle of a pole affects the position of contact wire relative to the level of the rail head. It is proposed to take into account a change in position of supporting constructions on the static parameters of catenary in high-speed Railways.

The article outlines modern approaches to determining the maximum permissible continuous current of current collectors when stopping and in motion. The features of techniques that reliably take into account operational factors when conducting tests in laboratory conditions are considered. A mathematical model is given for studying the distribution of current load in emergency mode of breaking a current-carrying shunt.

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.

Currently, according to regulatory documents, the resistivity of power line wires is assumed to be the same for any permissible load current and the heating temperature of the wires is equal to 20 degrees. This account of resistivity causes significant errors that significantly affect the operating modes of power transmission lines. This article analyzes the influence of outdoor air temperature, load current, solar radiation intensity, wind speed and direction on the heating temperature of overhead power lines, and as a result, on the value of the resistivity of the wires and power and electricity losses in them. The example of the BAM highway shows that even in the conditions of one region, the outdoor air temperature varies, depending on the time of year, within a very wide range. This in turn requires careful consideration of the dependence of the resistivity value of the line wires on the external air temperature. At the same time, it is shown that it is permissible to ignore the intensity of solar radiation, wind speed and direction on the heating temperature of overhead power lines due to the lack of comprehensive information about these factors and their opposite direction. However, this assumption will only be valid for operating currents in the range from zero to double the current value corresponding to the economic density. When calculating power losses, especially in heavily loaded lines, it is necessary to take into account all external temperature influences. Due to the appearance of sensor temperature sensors, it is proposed to use them directly to measure the heating temperature of line wires and then calculate their resistivity.

The use of new self-supporting insulated wires and high-temperature wires in the operation of power lines allows increasing the capacity of lines and, as a rule, reducing operational costs. An optimal utilization of the power line load capacity depends on the precise determination of the permissible current loads. The values of permissible currents and steady-state temperature are the main parameters of the line operating mode, affecting the strength and sag of the conductor. The temperature of the wire depends on weather conditions and current load. There are methods for determining the temperature and permissible currents for widely used traditional wires such as AC. They are partially outlined in the EIS (Electrical Installation Standard) and the standard of PJSC FGC UES (Federal Grid Company of Unified Energy System) of 2013. However, there is lack of studies in new types of wires. The paper considers the effect of weather conditions and load on the temperature and real-power losses in insulated and high-temperature wire, and solar radiation is under special consideration. For comparison, we present the results of calculations on traditional AC wires. The research shows that solar radiation, being taken into account, provides an increase of real-power losses of about 2 % with the given values of load and weather conditions. Calculations of permissible current values according to the developed technique for classical AC wires reveal a high coincidence with the values from PJSC FGC UES standard. The relative error is within two percent, and the proposed method is more generalized. It allows simultaneous analysis of both uninsulated and insulated wires. Due to the widespread use of self-supporting insulated wires, power industry experts can use the developed software in the design and operation of modern power lines to optimize capacity.