发明名称 |
Negative sequence differential element |
摘要 |
A negative sequence differential element may detect a fault in an electrical power system by computing a differential between negative sequence values derived from a first phase-current measurement and a second phase-current measurement. A transformer may be disposed between the first phase-current and second phase-current measurement location. The first phase-current measurement and the second phase current measurement may be normalized and a negative sequence current may be calculated therefrom. The negative sequence currents may be used to calculate an operating quantity, which may be an absolute value of the sum of the first and second negative sequence currents, and a restraint quantity comprising a maximum of the first and second negative sequence currents. The restraint quantity may be scaled by a slope factor. A fault may be detected if the operating quantity exceeds the scaled restraint quantity and a pickup current threshold. Three-Phase Transformer 115 14> 145 1221 r120 150- 152 Figure 1 |
申请公布号 |
AU2009200391(B2) |
申请公布日期 |
2013.07.04 |
申请号 |
AU20090200391 |
申请日期 |
2009.02.03 |
申请人 |
SCHWEITZER ENGINEERING LABORATORIES, INC. |
发明人 |
FISCHER, NORMANN;LABUSCHAGNE, CASPER |
分类号 |
G01R29/027 |
主分类号 |
G01R29/027 |
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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