ABB Relion 670 series - Page 465

R
X
Apparent
impedance at
normal load
Z
C
Z
A
Z
B
anglePhi
IEC07000015_2_en.vsd
IEC07000015 V2 EN
Figure 236: Impedances to be set for pole slip protection
The setting parameters of the protection is:
Z
A
: Line + source impedance in the forward direction
Z
B
: The source impedance in the reverse direction
Z
C
: The line impedance in the forward direction
AnglePhi : The impedance phase angle
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
1MRK 506 369-UUS - Section 8
Impedance protection
Line distance protection REL670 2.2 ANSI 459
Application manual