Zemskyi D. Increasing electricity transmission efficiency for non-traction consumers of alternating current railways

The relevance of the topic is due to the problems of efficient use energy resources and ensuring reliability of the equipment. In the power industry, one of the ways to solve these problems are to losses of electricity and ensure electromagnetic compatibility of devices. The electric rolling stock of AC railways are a powerful non-linear consumer, which has an asymmetric effect on three-phase networks and generates higher harmonics to external and non-traction power supply systems. Equipment of non-traction consumers supplying from the line, which is galvanically connected to the traction network, also known as, the “two wire-rail” line or TWR line, are in the worst electromagnetic conditions. Reducing the efficiency of electric power transmission to consumers in the concept of electromagnetic compatibility occurs through a combination of conductive and field effects on the TWR line. Addition, in most cases, it is not possible to provide bilateral power supply from the TWR lines that increases the loss of electricity when it is transmitted by the line. The values of the voltage unbalance indicator and total harmonic distortion in the TWR lines are 7,5… 10,6 % and 8.5 … 12,7 % but these rates are limited to 4 % (voltage unbalance) and 8 % (total harmonic distortion) in other non-traction power supply lines. Annua losses are 6 million kWh in TWR lines of Uralian railways. The total length of TWR lines in Ukraine is 4 thousand km, which is 80 % of the length of AC Railways. The annual volume of transmitted TWR lines is about 250 million kW.h. Due to the proliferation of DWP lines by AC railways and the disadvantages identified above, object of study is the process of transmission of electricity by lines galvanically connected to the traction network. The subject of the study is the efficiency of electricity supply, which is meant the transmission of electricity with the lowest losses and the deterioration of its quality. Accordingly, the purpose is to increase the transmission electricity efficiency by lines that are galvanically connected to the traction network.