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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.

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 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.

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.