Apparatus for detecting and controlling ferro-resonance of potential transformer

摘要

detect and suppress resonance of the transformer iron device according to the invention, the video voltage occurs only due to earth fault ground fault protection logic circuit for generating a protection relay contact output that is used for the circuit breaker trips to block the circuit breaker ( 1) and , if due to the resonance of the iron PT image voltage is generated by detecting the iron resonance protection relay for resonance suppression and resonance detection logic circuit (2) equipped with a protection logic circuit consisting of a resonance image detection unit 10 to generate a contact output ; The resonance detection logic protective relay contact output is output from the circuit 2 is applied to the protective relay contact is configured by including a resonance suppressing circuit (3) to suppress the resonance by the resistance subsequently installed . ;