ABB Relion 670 series, Technical Reference Manual

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A-G B-G C-G
A-G B-G C-G
A-G B-G C-G
A-G B-G C-G
A- B B-C C-A
A- B B-C C-A
A- B B-C -A
A- B B-C C-A
A-G B-G C-G A- B B-C C-A
Zone 1
Zone 2
Zone 3
Zone 4
Zone 5
C
Zone 6
A-G B-G C-G A- B B-C C-A
ANSI05000458-2-en.vsd
ANSI05000458 V2 EN
Figure 88: The different measuring loops at phase-to-ground fault and phase-to-
phase fault
The use of full scheme technique gives faster operation time compared to switched
schemes which mostly uses a pickup of an overreaching element to select correct
voltages and current depending on fault type. Each distance protection zone performs
like one independent distance protection IED with six measuring elements.
6.2.2.2 Impedance characteristic
Distance measuring zone, quadrilateral characteristic for series compensated lines
(ZMCPDIS, 21) include six impedance measuring loops; three intended for phase-to-
ground faults, and three intended for phase-to-phase as well as, three-phase faults.
The distance measuring zone operates according to the non-directional impedance
characteristics presented in figure
89 and figure 90 . The phase-to-ground characteristic
is illustrated with the full loop reach while the phase-to-phase characteristic presents
the per-phase reach.
1MRK505222-UUS C
Section 6
Impedance protection
197
Technical reference manual