ABB REG670 Applications Manual page 274

Section 8
Impedance protection
268
Z
B
IEC07000015 V2 EN
Figure 138: Impedances to be set for pole slip protection
The setting parameters of the protection is:
Z :
A
Z :
B
Z :
C
AnglePhi :
Use the following data:
UBase : 400 kV
SBase set to 1000 MVA
Short circuit power at station 1 without infeed from the protected line: 5000 MVA (assumed to a pure
reactance)
Short circuit power at station 2 without infeed from the protected line: 5000 MVA (assumed to a pure
reactance
Line impedance: 2 + j20 ohm
With all phase voltages and phase currents available and fed to the protection IED, it
is recommended to set the MeasureMode to positive sequence.
The impedance settings are set in pu with ZBase as reference:
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
X Z
A
Z
C
anglePhi
Line + source impedance in the forward direction
The source impedance in the reverse direction
The line impedance in the forward direction
The impedance phase angle
1MRK 502 071-UEN -
Apparent
impedance at
normal load
R
IEC07000015_2_en.vsd
Application manual