Impedance Characteristic - ABB RELION 670 Series Technical Manual

Section 7
Impedance protection
Figure 71
measuring zones. There are 3 to 5 zones depending on product type and variant.
A-G
A-G
A-G
A-G
A-G
A-G
ANSI05000458 V2 EN-US
Figure 71:
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.
7.1.7.2

Impedance characteristic

The distance measuring zone includes 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 will essentially operate according to the non-directional impedance
characteristics presented in figure
illustrated with the full loop reach while the phase-to-phase characteristic presents the per phase
reach.
184
presents an outline of the different measuring loops for up to five, impedance-
B-G C-G
B-G C-G
B-G C-G
B-G C-G
B-G C-G
B-G C-G
The different measuring loops at phase-to-ground fault and phase-to-phase
fault.
A- B B - C
A- B B -C
A- B B-C
A- B B-C
A- B B -C
A- B B - C
72 and figure 73. The phase-to-ground characteristic is
1MRK 502 066-UUS B
Zone 1
C-A
Zone 2
C- A
Zone 3
C -A
Zone 4
C -A
Zone 5
C -A
Zone 6
C-A
ANSI05000458-2-en.vsd
Technical manual
M16923-100 v7