Controlling non-sinusoidal modes of systems of railway electric power supply based on active harmonic filters

Abstract

The article presents the results of computer studies aimed at determining the efficiency of the use of active harmonic filters to control non-sinusoidal modes in the systems of AC railway electric power supply. A system of electric power supply of a double-track railway line with a length of 376 km was considered. It consisted of a 110-220-500 kV supply main and a 25 kV traction electric power supply system including eight traction substation and seven intersubstation zones. The movement of 15 up and down trains was simulated. Their masses were within a range of 1600…7100 tons. The results obtained make it possible to formulate a conclusion about the fact that the permissible values of total harmonic distortion of voltage are achieved when installing 25 kV active filters, designed to compensate effective currents of higher harmonics of 250 A, from the both sides of each intersubstation zone except for the one on which compensation filter devices are installed. Similar results can be obtained when installing three-phase filters in the 220 kV buses of railway line traction substations, though this variant requires higher costs. Besides, three-phase devices are known by a more complex control system and a lesser reliability.