发明名称 |
An apparatus and method for detecting the loss of a current transformer connection coupling a current differential relay to an element of a power system |
摘要 |
Disclosed is an apparatus and method for detecting a loss of a current transformer connection coupling a protective relay to a power system element of a three-phase power system and providing a plurality of secondary current waveforms of the three-phase power system to the protective relay. The apparatus includes a first logic circuit and a second logic configured to provide corresponding first and second binary signals in response to respective comparisons of calculated current value(s) of a plurality of like-phase digitized current sample streams to respective threshold values. The apparatus also includes a set reset flip-flop having a set input adapted to receive the first and second binary signals to provide a third binary signal. The third binary signal indicates loss of a current transformer connection when the set input is asserted and indicates no loss of a current transformer connection when the reset input is asserted. |
申请公布号 |
ZA200707274(B) |
申请公布日期 |
2008.12.31 |
申请号 |
ZA20070007274 |
申请日期 |
2006.02.27 |
申请人 |
SCHWEITZER ENGINEERING LABORATORIES, INC. |
发明人 |
GUZMAN-CASILLAS, ARMANDO;FISCHER, NORMANN |
分类号 |
H02H |
主分类号 |
H02H |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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