ABB Relion 670 Series RES670, Technical Manual

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1. When polMethod = Voltage , VPol will be used as polarizing quantity.
2. When polMethod = Current , IPol will be used as polarizing quantity.
3. When polMethod = Dual , VPol + IPol · ZNPol will be used as polarizing quantity.
The operating and polarizing quantity are then used inside the directional element, as
shown in figure
57 , in order to determine the direction of the ground fault.
PUREV
0.6 * INDirPU
PUFW
-RCA -85 deg
40% of
INDirPU
INDirPU
RCA
65°
VPol = -3V
0
I = 3I
op 0
RCA +85 deg
RCA -85 deg
Characteristic
for PUREV
Characteristic
for PUFW
Characteristic for reverse
release of measuring steps
Characteristic for forward
release of measuring steps
-RCA +85 deg
ANSI11000243-1-en.ai
Operating area
Operating area
ANSI11000243 V1 EN
Figure 57: Operating characteristic for ground-fault directional element using the
zero sequence components
Two relevant setting parameters for directional supervision element are:
• Directional element will be internally enabled to trip as soon as Iop is bigger than 40%
of
IDirPU and directional condition is fulfilled in set direction.
• Relay characteristic angle AngleRCA , which defines the position of forward and
reverse areas in the operating characteristic.
1MRK 511 365-UUS A
Section 8
Current protection
Phasor measurement unit RES670 2.1 ANSI 205
Technical manual