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On the basis of the analysis of statistics of the incidents which have occurred on the railroads of Russia and connected with collisions of trains with obstacles, the most probable scenarios of development of an emergency situation are allocated. Modern methods of investigation of kinematics and dynamics of vehicles are analyzed. By methods of solid-state computer modeling the estimation of the dynamic loadings acting on the locomotive and passenger cars at collision of the passenger train with an obstacle in the form of the lorry on the railway crossing is carried out. For this purpose solid-state computer model of a passenger train and a cargo car. The obtained results indicate a high dynamic load of the locomotive in a collision. At the same time, passenger cars are affected by low dynamic loads that do not lead to damage to the load-bearing structures of passenger cars. The obtained results can be used in the creation of modern passenger rolling stock, characterized by high demands on safety in emergency situations. The work was carried out within the grant of the President of the Russian Federation for the state support of young Russian scientists MK-2881.2018.8.

One of the properties of the reliability of the power supply of electric rolling stock of railways is the trouble-free operation of the traction power supply system in various modes of its operation. For post-emergency and forced modes of operation of the traction power supply system, a decrease in load capacity is characteristic. In order to ensure the throughput and carrying capacity of the railway section by traction power supply devices, it is proposed to consider the use of electric power storage devices on electric rolling stock and in the traction power supply system. Studies conducted by domestic and foreign researchers allow us to evaluate the effectiveness of alternative solutions to improve the reliability of power supply, which include various options for the use of electric power storage devices on electric rolling stock and in the traction power supply system. This article presents the results of a review of these solutions, a simulation model of a traction power supply system and an electric rolling stock with power storage devices based on various batteries and a supercapacitor is proposed. Modeling of changes in the modes of operation of the traction power supply system is carried out taking into account the state control of switching devices. The calculation results allow us to estimate the voltage drop at the output of electric power storage devices, including taking into account the exponential zone of the discharge characteristics of batteries, to estimate the voltage change for a given electric traction load depending on the energy intensity of the storage device, made on the basis of the most common types of batteries and a supercapacitor.

In connection with the traceable global trend of increasing average speeds in railway transport, more and more often they are trying to exclude the intersection of railways and roads. However, in the Russian Federation, only 40 % of railway crossings are located near settlements or on busy roads, the construction of two-level interchanges at the remaining crossings is not economically profitable, and sometimes difficult due to climatic conditions. Therefore, a different approach is needed to prevent incidents and accidents at crossings. At the same time, the need for an individual construction of a security strategy for each object of the transport infrastructure should be taken into account. At present, in the existing information systems of the Ministry of Transport, the Ministry of Internal Affairs, as well as the owners of the railway infrastructure, a fairly large amount of statistical information has been accumulated on incidents and traffic accidents at railway crossings. But most often these data are used for certificates containing absolute values in each of the departments. At the same time, the relationships between these disparate sources of information are not comprehensively analyzed. Modern technologies for creating intelligent information systems based on existing large databases and tools such as machine learning, intelligent search, neural networks make it possible to build an expert system based on a specific set of rules that can analyze the situation at a particular crossing, assess the likelihood of emergency situations and suggest ways to prevent them. In addition, it is important to analyze not only the infrastructure, but also specific units of vehicles and the accident-free performance of the drivers driving them. This article discusses the prerequisites and technology for building a knowledge base of an intelligent system used to analyze the level of safety at railway crossings, which will allow us to combine currently information about the factors accumulated in various systems that affect traffic safety at crossings and based on the accumulation of knowledge give a forecast of the development of the situation at each specific object.

Researching subject which are presented in article is the emergency modes in 25 kV traction power supply systems caused by the short circuits (SC). The research purpose consisted in the analysis of calculation SC currents errors evolving from the reactances determined by SC power at the simplified modeling of external network. For achievement of formulated purpose comparative calculations of SC currents for a number of standard schemes of 25 kV system when using full models in phase coordinates and with use of simplified electric power system (EPS) reactances are executed. Modeling has shown that calculations of SC currents of contact network of deadlock substation by EPS reactances give the acceptable accuracy for feeder current of substation near which there is a short circuit. The calculation error of remote substation feeder current can reach +100% at SC power on inputs of substation about 300 MV·A, but decrease to values about 10% at the SC power of 2500 … 3000 MV·A. At food of group of traction substations from two 110 kV lines calculation error for equivalent reactances it is much less, however at SC power about 300 MV·A errors reach 35% and decrease to 10% at SC power on substation inputs more than 550 MV·A. Variant of traction substations power supply from two 220 kV power lines differs in small calculation errors of SC currents for equivalent external power supply reactances: differences from full scheme don't exceed 9% at SC powers of 1200 MV·A or more. The received results can be used at improvement existing and creation of new definition techniques for SC currents in 25 kV traction networks.