ABB REL650 series, Техническое руководство

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6.2.6.6 Simplified logic diagrams
Figure 61 presents schematically the creation of the phase-to-phase and phase-to-ground
operating conditions. Consider only the corresponding part of measuring and logic
circuits, when only a phase-to-ground or phase-to-phase measurement is available within
the IED.
ANSI09000149-2-en.vsd
AND
AND
AND
Bool to
integer
DLECND
STPG
STPP
IRELPG
IRELPP
BLOCK
AND
Load encroachment block
0
20ms
0
10ms
0
15ms
0
15ms
0
3 I IMinPUPG
<
0 max
3 0 _
3
100
I BLK PP
I Iph
< ×
0
3 0.5 I IMinPUPG
³ ×
0
3 0 _
3
100
max
I Enable PG
I Iph
³ ×
ANSI09000149 V2 EN
Figure 61: Phase-to-phase and phase-to-ground operating conditions (residual
current criteria)
A special attention is paid to correct phase selection at evolving faults. A DLECND output
signal is created as a combination of the load encroachment characteristic and current
criteria, refer to figure
61 . This signal can be configured to STCND functional input
signals of the distance protection zone and this way influence the operation of the phase-
to-phase and phase-to-ground zone measuring elements and their phase related pickup
and tripping signals.
Figure 62 presents schematically the composition of non-directional phase selective
signals NDIR_A (B or C). Internal signals ZMn and ZMmn (m and n change between A,
B and C according to the phase) represent the fulfilled operating criteria for each separate
loop measuring element, that is, within the characteristic.
Section 6
1MRK 506 335-UUS A
Impedance protection
142
Technical manual