ABB Relion 670 series, Technical Manual

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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-US
Figure 255: 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.
Directional comparison step, built-in within directional supervision element, will set EF4PTOC
(51N/67N) function output binary signals:
1. PUFW=1 when operating quantity magnitude Iop x cos(φ - AngleRCA) is bigger than setting
parameter IDirPU and directional supervision element detects fault in forward direction.
2. PUREV=1 when operating quantity magnitude Iop x cos(φ -
AngleRCA) is bigger than 60% of
setting parameter
IDirPU and directional supervision element detects fault in reverse
direction.
These signals shall be used for communication based ground-fault teleprotection communication
schemes (permissive or blocking).
Simplified logic diagram for directional supervision element with integrated directional
comparison step is shown in figure 256 :
1MRK 502 066-UUS B Section 8
Current protection
485
Technical manual