DEVICE TO PROTECT RECTIFIER SETS OF TRACTION SUBSTATIONS AGAINST NON-SYMMETRICAL EXTERNAL AND INTERNAL SHORT CIRCUITS

摘要

FIELD: electricity.;SUBSTANCE: device comprises a reverse sequence filter made on two intermediate current transformers (CT). Primary windings of the first intermediate CT are connected for a difference of currents of two phases, and the primary winding of the second one is connected into the third phase, the secondary winding of the first intermediate CT is connected to the first loading resistor and a resistor serially connected to a capacitor to form a phase-shifting circuit, and the middle point is connected with one of outputs of the secondary winding of the second intermediate CT loaded onto the second loading resistor, the second output of the secondary winding and a point of connection of the resistor and the capacitor being the filter output are connected to the input of a comparison element connected to the first threshold element, to the output of which via the "AND" element an execution protection element is connected, besides, the input of the execution protection element is connected via the "AND" element to the second threshold element, the input of which via a filter of the first harmonic is connected to a current sensor of a rectifier reverse circuit.;EFFECT: higher noise immunity and reliability.;3 cl, 5 dwg