FIELD: electrified railways. SUBSTANCE: proposed device has pickup of traction current harmonic components and signal processing unit with n- section unit of phase shifting elements connected by information inputs to corresponding outputs of traction current selector, and by control inputs to corresponding outputs of first n-section phase shift controller unit, first n-section scaling unit with scaling factor Ks (comp) connected by inputs to corresponding outputs of first unit of phase shifting elements, and mixer. Device includes also adjustable current source coupled by control input with mixer output and inserted at break of shielding wire grounded at ends and located between contact system and line exposed to electromagnetic effects. As distinct from known devices, proposed device has feedback channel with pickup of harmonic components of shielding wire compensating current, second n- section selector of compensating current, n- section phase shift controller unit, second n- section unit of phase-shifting elements and second n- section scaling unit with scaling factors Ks (fb). Scaling factors for scaling units are selected to provided the following relation: Ks (comp) - Ks (fb) = 1. Device provides higher protection in any range of contact system current harmonics by forming compensating current by compensating current parameters negative feedback. EFFECT: reduced electromagnetic influences on communication lines. 1 dwg, 1 an
