| 摘要 |
<p>The present invention is concerned with a method for faulted phase selection and fault type determination in electric power lines applicable both to series compensated and uncompensated power lines, fit for use in the power industry for overhead and overhead-cable transmission or distribution lines. The inventive method comprising the following steps: a fault inception detection, an estimation of fault phase current signals, pre-fault current signals and zero-sequence current in order to receive the absolute value of incremental current signals (I AB , I BC , I CA ) and their maximum value (I max ), a calculation of real value indicators ( S A ,S B ,S C ,S 3 A ,S 3 B ,S 3 C ) which indicate the minimum values of a combination of data for phase to phase faults and for 3-phase fault and a calculation of a real value indicator ( S G ) as the maximum value of data for phase to ground fault, a calculation of the fault type indicators (F1 -F10) as the minimum values of the real values indicators ( S A ,S B ,S C ,S 3 A ,S 3 B ,S 3 C ,S G ) by: grouping the first group indicators (F1-F3) and calculating the sum of the minimum value of the combination of real value indicators for phase to ground fault, grouping the second group indicators (F4-F6) and calculating the minimum value of the combination of real value indicators for phase to phase fault, grouping the third group indicators (F7-F9) and calculating the sum of the previously calculated indicator (F1-F6) for phase to phase to ground faults, calculating the indicator (F10) as the minimum value of real value indicators for 3-phase fault, a selection of a fault phase (F max ) by calculating the maximum value of all the fault type indicators (F1-F10) which at the same time determines the fault type and presentation of the data in the protective relay (2) or in the means connected to the protective relay.</p> |
