ABB REG650 Technical Manual page 295

1MRK 502 043-UUS B
Technical Manual
Beta
ç V3N ç
X
ç V3N+V3T ç
VT3BlkLevel
ç V3T ç
VNFundPU
V_N
ANSI07000001 V2 EN
Figure 133: 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 134.
-
- DV
- V +
3N
ANSI07000002 V2 EN
Figure 134: 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
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+
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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