FIELD: electrified railway transport; current filtering devices. SUBSTANCE: active filter has at least two bridges with force switching and voltage source. Bridges are connected in series at side of ac current and are independently energized with DC voltage. Filter includes also control element providing forced switching of bridges to provide ac current from different voltage levels at side of single phase current. These voltages are resulting combinations of values of bridge DC voltages. Current, thus obtained, is supplied to collectors and distributors for compensation of harmonics and consumed reactive power arising at operation of traction and auxiliary equipment and getting into overhead contact system. EFFECT: improved reliability of operation. 17 cl, 6 dwg
