Search results

The article substantiates the need to update the normative documentation for the selection of smoothing devices for DC traction substations. General requirements for smoothing devices, labor protection and electromagnetic safety requirements are formulated. The main schemes of smoothing devices used at DC traction substations are considered. Recommendations have been developed for the selection of smoothing device schemes for the modernization and construction of new traction substations, taking into account their energy efficiency.

The article discusses the solution of problems related to the development of a simulation model of a DC traction substation designed to evaluate energy and other performance indicators, including electricity quality indicators. The development of a simulation model makes it possible to evaluate the effectiveness of technical measures that can be used at traction substations to solve problems of improving the quality of rectified voltage, reducing non-sinusoidal busbars for their own needs, regulating the voltage on substation tires, and a number of others. Currently, the urgent tasks in the field of non-traction power supply include reducing the non-sinusoidal voltage on the busbars of alarm, centralization and blocking consumers who are sensitive to high voltage harmonics. The simulation was performed for one of the most common circuit solutions, characterized by the fact that a twelve-pulse rectification circuit of a sequential type is used at the substation. The proposed model was developed in the SimInTech software environment and allows you to evaluate the performance of a substation for various circuit states using switches inserted into the circuit. The simulation results are given for a symmetric system of sinusoidal voltages. The simulation results are compared with the results obtained on the basis of an experimental assessment of electricity quality indicators for one of the operating DC traction substations. The above measurement results at a traction substation with twelve-pulse rectifiers of a sequential type were performed synchronously for two pairs of inputs of 0.4 and 10 kV of the traction substation. A comparison of the simulation results shows the adequacy of the developed model and the equipment characteristics used in it, which makes it possible to use it to solve a number of other tasks.

Recently, during overhaul of the railway track using modern materials such as geotextiles and penoplex. In turn, they make significant changes to the structure of the ballast, t. To. Are almost insulators. OSTU experimentally it has been ascertained that the contact resistance in the case of using a new type of cloth can be raised to 45 - 150 Om*km. Obviously, this leads to a significant increase in the capacity of the rail relative to a distant ground and can cause injury to personnel operating the traction members network. To determine the capacity of the rail at any point area must take into account the redistribution of power in the elements of the rail network, ie. E. In the rail and the transition resistance «rail - the land». The rail network is characterized by longitudinal rails Zp kilometricheskim resistance, transition resistance «rail - land» rp-s, and the characteristic impedance ZB kilometricheskim spreading factor γ rail network. Analysis of the results lead to the following conclusions: 1) contact resistance «rail-to-earth» has a significant impact on the value of the potentials arising on the elements of reverse current flow circuit; 2) the growth of the resistance «rail-to-earth», associated with seasonal fluctuations in soil resistivity, as well as in recent times, with the capital reconstruction of the roadbed, resulting in a significantly longer (up to several tens of kilometers) area, for which the potential can reach hazardous the value of human life; 3) in the circuit mode on a rail (m. E. When a metal short circuit) almost always rail network will occur potentials exceeding admissible values for several kilometers in both directions from the point of fault, which leads to removal of the dangerous potential at all metal construction connected with the rail and therefore requires a review of the principles of grounding structures.