ABB Relion 650 Series Technical Manual page 280

Section 9
Secondary system supervision
A drop off delay of 100 ms for the measured zero-sequence and negative sequence current will
prevent a false fuse failure detection at un-equal breaker opening at the two line ends.
Sequence Detection
3I0PU
IA
IB
IC
3I2PU
3V0PU
VA
VB
VC
3V2PU
ANSI10000036 V1 EN-US
Figure 140: Simplified logic diagram for sequence detection part
The calculated values 3V
monitoring tool in PCM600.
9.2.7.2 Delta current and delta voltage detection
A simplified diagram for the functionality is found in figure 141. The calculation of the change is
based on vector change which means that it detects both amplitude and phase angle changes.
The calculated delta quantities are compared with their respective set values
the algorithm, detects a fuse failure if a sufficient change in voltage without a sufficient change in
current is detected in each phase separately. The following quantities are calculated in all three
phases:
• The change in voltage DV
• The change in current DI
The internal FuseFailDetDVDI signal is activated if the following conditions are fulfilled for a phase:
• The magnitude of the phase-ground voltage has been above
• The magnitude of DV is higher than the corresponding setting
• The magnitude of DI is below the setting
and at least one of the following conditions are fulfilled:
• The magnitude of the phase current in the same phase is higher than the setting
• The circuit breaker is closed (52a = True)
274
Zero
sequence
filter
a
a>b
b
Negative
sequence
filter
a
a>b
b
Zero
a
sequence a>b
b
filter
Negative
a
sequence
a>b
b
filter
, 3I , 3I and 3V
0 0 2
© Copyright 2011 ABB Power Grids. All rights reserved
100 ms
t
FuseFailDetZeroSeq
AND
100 ms
t
FuseFailDetNegSeq
AND
are available as service values on local HMI and
2
DIPU
1MRK 506 326-UUS B
CurrZeroSeq
3I0
CurrNegSeq
3I2
VoltZeroSeq
3V0
VoltNegSeq
3V2
ANSI10000036-1-en.vsd
GUID-DEDFECAD-652F-4D25-A649-A41E65D0580B v2
DIPU and DVPU and
VPPU for more than 1.5 cycle
DVPU
50P
Line distance protection REL650
Technical manual