Electricity: electrical systems and devices – Safety and protection of systems and devices – Transformer protection
Patent
1983-06-06
1984-10-16
Salce, Patrick R.
Electricity: electrical systems and devices
Safety and protection of systems and devices
Transformer protection
361 87, 361113, H02H 7045
Patent
active
044778546
ABSTRACT:
A relay adapted for protection of a transformer and capable of functioning with certainty upon occurrence of any internal fault in the transformer but not functioning in the case of an inrush current which flows therein at the time of non-load energization or the like. The relay comprises a ratio differential element for comparing the amount of a suppression current with that of a differential current flowing in the transformer, an element for detecting the content proportion of a second harmonic component in the differential current, a monostable multivibrator for sending an output of a fixed pulse width at the moment of detection of the differential current, an AND circuit for producing an output in accordance with the logical product condition relative to the output of the second-harmonic detection element and that of the monostable multivibrator, a timing circuit for producing an output when the output of the second-harmonic detection element continues for a predetermined period of time, and gate means for suppressing the output of the ratio differential element when either the output of the AND circuit or that of the timing circuit is being fed thereto.
REFERENCES:
patent: 3323016 (1967-05-01), Andersson
patent: 4204237 (1980-05-01), Zocholl
patent: 4402028 (1983-08-01), Udren
Westinghouse I.L. 41-347.1H--Types HU and HU-1 Transformer Differential Relays.
ASEA Catalogue RK 62-10 E--Transformer Differential Relay Type RADSE.
General Electric Company Limited Bulletin "GEC Measurements".
Honma Akiyoshi
Usui Masaji
Mitsubishi Denki & Kabushiki Kaisha
Salce Patrick R.
LandOfFree
Portective relay with second harmonic suppression does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Portective relay with second harmonic suppression, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Portective relay with second harmonic suppression will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1948142