发明名称 |
SYSTEM FOR PREVENTING UNDESIRED PROTECTIVE RELAY TRIPPING ACTIONS DUE TO COUPLING CAPACITOR VOLTAGE TRANSFORMER TRANSIENTS |
摘要 |
The system impedance ratio (SIR) is determined for the original zone 1 distance element reach (116) of a protective relay (132). The reduction in the original zone 1 reach is then determined (120), using the SIR value (118) and a known table of reduced values. When a fault is recognized the minimum reach (126) to just detect the fault is determined. A trip signal (130) is provided without any delay if the minimum reach (126) is less than or equal to the reduced reach (120). The trip is delayed (136) for a selected time if the minimum reach (126) is greater than the reduced reach (120) but not greater than the original reach (116).
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申请公布号 |
WO9921260(A1) |
申请公布日期 |
1999.04.29 |
申请号 |
WO1998US21564 |
申请日期 |
1998.10.13 |
申请人 |
SCHWEITZER ENGINEERING LABORATORIES, INC. |
发明人 |
GUZMAN-CASILLAS, ARMANDO;ROBERTS, JEFFREY, B. |
分类号 |
H02H1/00;H02H1/04;H02H3/04;H02H3/40;(IPC1-7):H02H3/38 |
主分类号 |
H02H1/00 |
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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