Abstract
The article is devoted to the problem of improvement of the service lifetime of power transformers in the train moving traffic system. The connection of the traction substation to the contact network according to the auxiliary supply source scheme is analyzed in the article. This circuit design does not correspond to the classical connection scheme in the power supply system of the 25 kV alternating current. Power transformers in the power supply system of electrified railways (ELR) with the wattage of, as a rule, 40 MVA are quite expensive. Modern power transformers in the AC power supply system comply with the standards and are characterized by the parameters of the transformers produced in the past. Thus, the use of new transformers by replacing previously installed ones leads to significant capital investments. At the same time, the results of the operation of new power transformers cannot lead to an increase in economic traction power supply system of the 25 kV AC values according to the accepted connection schemes. The instantaneous current values of traction loads are taken as real in order to perform a qualitative assessment of the efficiency of the circuit. Constant phasing of neighboring traction substations is a limitation of the choice of the scheme connected to the contact network according to the auxiliary supply source scheme. Normalization of the distribution current traction loads, when the traction substation is connected to the contact network according to the classical scheme, was proved. The coupling of the traction network of the intersubstation zone is made using a sectioning post connected according to the "quadrangle" scheme. Traction loads are powered according to the looping scheme. An increase in the service lifetime of power transformers was proved by a significant decrease in the temperature of the hottest point of the winding when the transformer is connected according to the classical scheme.
Keywords
Power transformer, power supply system, service lifetime, insulation deprecation, section switch box.
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