POWER FILTER (VERSIONS) Russian patent published in 2010 - IPC H02M1/16 

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and aims at increasing noise immunity of relay protection and automatic control circuitry fed from DC and AC lines. For this the circuit incorporates the filter comprising inductor coils no ferromagnetic cores and capacitors making LC-components in general noise circuit, additional key resistive two-pole networks to shunt inductor coils. Said resistive two-pole networks connected during high-voltage pulse existence bring about extra losses to limit transition currents in inductor coils and voltage surge in capacitors.

EFFECT: higher reliability.

9 cl, 4 dwg