ABB Relion Technical Manual page 323

1MRK 502 048-UUS A
Technical manual
Beta
ç V3N ç
X
ç V3N+V3T ç
VT3BlkLevel
ç V3T ç
VNFundPU
V_N
ANSI07000001 V2 EN
Figure 146: Simplified Pickup and Trip logical diagram of the STEFPHIZ (59THD)
protection
There are two different cases of generator block configuration; with or without generator
circuit breaker. If there is no generator breaker the capacitive coupling to ground is the
same under all operating conditions. When there is a generator breaker, the capacitive
coupling to ground differs between the operating conditions when the generator is running
with the generator breaker open (before synchronization) and with the circuit breaker
closed. This can be shown as in figure 147.
-
- DV
- V +
3N
ANSI07000002 V2 EN
Figure 147: Generator block with generator circuit breaker
a
b ³ a
b
AND
a
a ³ b
b
a
b ³ a
b
UV
3
+
3
Section 9
Voltage protection
t
0
OR
OR
t
0
ANSI07000001-2-en.vsd
+
+
V
3T,A
-
+
V
3T,B
-
+
V
3T,C
-
en07000002-2_ansi.vsd
PU3H
TRIP3H
PICKUP
TRIP
PU_VN
TRIPVN
Ctr/3
Ctr/3
Ctr/3
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