ABB REG650 Technical Manual page 141

1MRK 502 034-UEN -
Technical Manual
0.6
-
0.4
X-line -
-
determined
-
by the
→
^ ^ ^ ^
-
0.2
setting
-
ReachZ1
-
- -
0
Zone 1
-
-
-
-
-0.2
-
limit-of-reach
→
-
-
circle depends on
-0.4
the position of the
points SE and RE
-0.6
-0.8 -0.6 -0.4
IEC10000112 V1 EN
Figure 72: Construction of the lens characteristic for a power system
ReverseZ ReverseZ
Zgen(Rgen, Xgen) Zgen(Rgen, Xgen)
Generator Generator
13.8 kV 13.8 kV
13.8 kV 13.8 kV
G G
SE SE
Out-Of-Step Out-Of-Step
REG REG
protection protection
OOSPPAM OOSPPAM
IEC10000113 V1 EN
Figure 73: Example of an actual power system
To be able to automatically construct the lens characteristic for a system shown in
Figure 73, the actual power system must be modeled as a two-machine equivalent
system, or as a single machine – infinite bus equivalent system, the following
information is necessary: Zgen(Rgen, Xgen), Ztr(Rtr, Xtr), Zline(Rline, Xline),
Zeq(Req, Xeq), and the setting StartAngle, for example 120 degrees. All
impedances must be referred to the voltage level where the out-of-step protection
relay is placed; in this case shown in
X
-
- RE -
- -
- -
- - -
- -
- - - -
- - -
- - - -
- -
- - - -
- -
Ze
- -
- -
Zone 2
- -
- -
- -
- -
- -
- -
- -
Zline - -
- -
- -
- -
^ ^ ^ ^
- -
^ ^ ^ ^
- -
^ ^ ^ ^
- -
Ztr
- -
- -
- -
relay
- -
120°
- -
- -
- -
- -
Z-line
←
- -
- -
- -
Zgen
- -
- -
- -
- -
← Lens is the locus
- - - -
- -
- -
- -
of constant rotor (power)
- -
-
- - -
- -
-
- - -
- -
angle, e.g. 120°.
-
- - -
- -
- -
Lens' width determined
- -
- -
-
SE
by the setting StartAngle
-0.2 0 0.2
Real part (R) of Z in Ohms
ForwardZ(ForwardR, ForwardX) ForwardZ(ForwardR, ForwardX)
Ztr(Rtr, Xtr) Ztr(Rtr, Xtr) Zline(Rline, Xline) Zline(Rline, Xline)
Transformer Transformer
13.8 / 220 kV 13.8 / 220 kV
d d
Y Y
ReverseR = Rg ReverseR = Rg
ReverseX = Xd' ReverseX = Xd'
All impedances must be referred to the generator voltage 13.8 kV All impedances must be referred to the generator voltage 13.8 kV
Figure 73
Section 6
Impedance protection
Position of the OOS
relay is the origin of
-
the R - X plane
-
-
-
-
-
-
-
- -
-
- -
- -
-
^ ^
- -
R
- -
- -
- -
-
- -
-
Z(R,X)
-
-
-
-
-
-
-
-
0.4 0.6 0.8 1
IEC10000112-1-en.vsd
Zeq(Req, Xeq) Zeq(Req, Xeq)
Infinite power Infinite power
Power line Power line System System
220 kV 220 kV equivalent equivalent
ForwardR = Rtr + Rline + Req ForwardR = Rtr + Rline + Req
ForwardX = Xtr + Xline + Xeq ForwardX = Xtr + Xline + Xeq
IEC10000113-1-en.vsd
this is the generator nominal
system system
RE RE
135