ABB RELION 670 Series Technical Manual page 360

Section 7
Impedance protection
Z
K
=
N
IECEQUATION15017 V1 EN-US
0
Z
=
set
IECEQUATION15028 V1 EN-US
Z 1
=
set
IECEQUATION15029 V1 EN-US
where
Z 0
set
1
Z
set
R0FwPEZx
X0FwPEZx
R1FwPEZx
X1FwPEZx
For an earth fault in phase A, the angle
voltage
arg [
β =
ANSIEQUATION15021 V1 EN-US
where
V
A
I
A
3I
0
1
Z
set
V
pol
354
0 1
Z
−
set set
3 1
Z
⋅
set
0 0
R FwPEZx j X FwPEZx
+ ⋅
R FwPEZx 1 j X FwPEZx 1
+ ⋅
is,
V
pol
( 3 0 )
V I I K
− + ⋅ ⋅
A A N
is the phase voltage in faulty phase A
is the phase current in faulty phase A
is the zero-sequence current in faulty phase A
is the complex positive sequence impedance of the line in Ω/
phase for phase-to-ground fault in zone direction
is the polarizing voltage in phase A
is the complex zero sequence impedance of the line in Ω/phase
is the complex positive sequence impedance of the line in Ω/
phase
is the zero sequence resistive reach of the line in Ω/phase for
phase-to-ground fault in zone direction for zone x (x=1-5, or RV)
is the zero sequence reactance reach of the line in Ω/phase for
phase-to-ground fault in zone direction for zone x (x=1-5, or RV)
is the positive sequence resistive reach of the line in Ω/phase
for phase-to-ground fault in zone direction for zone x (x=1-5, or
RV)
is the positive sequence reactance reach of the line in Ω/phase
for phase-to-ground fault in zone direction for zone x (x=1-5, or
RV)
β between the compensation voltage and the polarizing
1 ] arg ( )
Z V
−
set pol
1MRK 502 066-UUS B
(Equation 105)
(Equation 106)
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