No abstract

The use of current-collecting contact elements with an extended service life is one of the most economical and least costly ways to ensure reliable, economical and environmentally friendly power transmission to the rolling stock. To assess and predict the service life, Omsk State Transport University developed and successfully tested a methodology for conducting experimental studies of contact inserts for pantographs, including bench tests of each pair of contact materials. The obtained test results are the initial data for predicting the wear of elements of contact pairs and assessing their service life in real operating conditions. Prediction of wear and service life of contact elements is carried out using mathematical modeling of wear processes, taking into account the maximum possible number of factors that negatively affect the elements. The purpose of this article is to improve the method for predicting wear, taking into account high speeds. The use of a mathematical model in forecasting makes it possible to reduce time and labor costs by 2.5 - 3 times for conducting experimental studies and assessing the resource of an element of a contact pair.

The long-term development program of the Russian Railways holding provides for a comprehensive modernization of the railway infrastructure by The least expensive of these measures is the use of contact elements with an extended service life, providing reliable, economical and environmentally friendly transmission of electricity to rolling stock. In accordance with the program developed and successfully tested at OSTU, the methodology for conducting experimental studies of contact pairs of current collector devices for conducting a test cycle requires specialized experimental complexes, as well as significant time and resources. To reduce the volume of experimental studies, a combined method is used - a combination of the required minimum of experimental studies of real objects (or their analogues) and calculation methods based on mathematical modeling of processes occurring in contact pairs of current collector devices. However, the use of existing mathematical models for predicting wear under conditions of very high-speed movement is not accurate enough due to the lack of consideration of the aerodynamic effects and the speed of the rolling stock on current collection processes. This article discusses the improvement of the electrical component of the wear model of the elements of contact pairs of current collector devices under conditions of very high-speed movement. The histograms of the electrical wear of contact elements obtained by calculation using the existing and improved mathematical models are presented.

Current collection quality is one of the limiting factors when increasing trains movement speed in the rail sector. With the movement speed growth, the impact forces on the current collector from the rolling stock and the aerodynamic influence increase, which leads to the spread in the contact pressure values, separation of the current collector head from the contact wire, contact arcing and excessive wear of the contact elements. The upcoming trend in resolving this issue is the use of the automatic control systems providing stabilization of the contact pressure value. The present paper considers the features of the contemporary automatic control systems of the current collector’s pressure; their major disadvantages have been stated. A scheme of current collector pressure automatic control has been proposed, distinguished by a proactive influence on undesirable effects. A mathematical model of contact strips wearing has been presented, obtained in accordance with the provisions of the central composition rotatable design program. The analysis of the obtained dependencies has been carried out. The procedures for determining the optimal current collector pressure on the contact wire and the pressure control principle in the pneumatic drive have been described.

The use of contact elements with an extended service life is one of the most economical and least costly ways to ensure reliable, economical and environmentally friendly transmission of electricity to rolling stock. To evaluate the service life in OSTU, a methodology for conducting experimental studies of contact pairs of pantograph has been developed and successfully tested, involving bench tests for each pair of contact materials “contact insert - contact wire” in order to determine their optimal combination to reduce wear and increase service life. Assessment of the amount of wear and prediction of the life of the contact elements are made, including using mathematical modeling. The purpose of this article is to improve the mechanical component of the wear model of the contact elements of pantograph in high-speed conditions. The results of experimental studies and theoretical calculations of the mechanical wear of contact elements are presented. The analysis of the graphs allows us to conclude that it is possible to use an improved mathematical model for modeling the mechanical component of the wear process of the elements of contact pairs with a maximum error value of not more than 5%.