ABB Relion 670 series, Technical Manual

Page: 320 / 1432

K
Z Z
Z
N
set set
set
=
−
⋅
0 1
3 1
IECEQUATION15017 V1 EN-US
Z R Zx j X Zx
set
0 0 0
= + ⋅
IECEQUATION15018 V1 EN-US
For Zone 1,
Z R PEZ j X PEZ
set
1 1 1 1 1
= + ⋅
IECEQUATION15019 V1 EN-US
For Zone 2-5 and RV,
Z R Zx j X Zx
set
1 1 1
= + ⋅
IECEQUATION15020 V1 EN-US
(Equation 90)
where
Z
set
0
is the complex zero sequence impedance of the line in Ω/phase
Z
set
1
is the complex positive sequence impedance of the line in Ω/
phase
R1PEZ1 is the positive sequence resistive reach of the line in Ω/phase
for phase-to-ground fault for zone 1
X1PEZ1
is the positive sequence reactance reach of the line in Ω/phase
for phase-to-ground fault for zone 1
R0Zx
is the zero sequence resistive reach of the line in Ω/phase for
zone x (x=2-5, or RV)
X0Zx is the zero sequence reactance reach of the line in Ω/phase for
zone x (x=2-5, or RV)
For an earth fault in phase A, the angle β between the compensation voltage and the polarizing
voltage
V
pol
is,
β = − + ⋅ ⋅ −
arg [ ( ) ] ( ) V I I K Z V
A A N set pol
3 0 1 arg
ANSIEQUATION15021 V1 EN-US
(Equation 91)
where
V
A
is the phase voltage in faulty phase A
I
A
is the phase current in faulty phase A
3I
0
is the zero-sequence current in faulty phase A
Z
set
1
is the complex positive sequence impedance of the line in Ω/
phase for phase-to-ground fault in zone direction
V
pol
is the polarizing voltage for phase A
Section 7 1MRK 502 066-UUS B
Impedance protection
314
Technical manual