ABB REB670 Series Applications Manual page 134

Section 6
Differential protection
6.1.5.2 Typical arrangement which can be covered
The six-zone busbar differential protection is intended for applications with complex
switchgear layout. In general, there are the following restrictions:
1. Up to six independent protection zones
2. Up to twenty-four CT inputs (depends on selected IED hardware)
3. Up to twenty-four feeder bays
4. Up to five bus interconnector (i.e. bus-ties) bays
5. For very large installation the total number of binary inputs and outputs, which can be
fitted in one IED, can also be a limiting factor. For such installations the possibility to
share the disconnector status among the three IEDs using communication (e.g. GOOSE or
LDCM) can be considered.
Five typical examples of busbar arrangements with up to six differential zones are presented
in Figure
example application shown in Figure
Z1
Z2
QB1
QA1
B11
Feeder 01-08
IEC16000142 V1 EN-US
Figure 71:
Z1
Z2
QB1
IEC16000143 V1 EN-US
Figure 72: Double busbar station with breaker bypass facility and four protection zones
128
71 - Figure 75. In the next section, the engineering procedure is described for the
Sectionalizing disconnectors
QB11
QB21
QB2 QB1 QB2 QB10
B11
QA1
Bus-Interconnector 1 with two CTs
Double busbar station with six protection zones
Sectionalizing disconnectors
QB2 QB1 QB2
QA1
QB7
QB9
B11
B11
Feeder 01-06 Bus-Interconnector 1 with two CTs
74 to illustrate the engineering principles.
Z3
Z4
QB20 QB2 QB20 QB1
QA1 QA1
B12 B14 B13
Bus-Interconnector 2 Bus-Interconnector 3
with one CT
QB11
QB21
QB10 QB20
B12
QA1
1MRK 505 370-UEN D
GUID-2BC52A24-7844-4F83-A11E-944FC3487582 v1
Z5
Z6
QB10 QB1 QB2
QA1
B11
Feeder 09-15
with one CT
IEC16000142-1.en.vsdx
Z3
Z4
QB1 QB2
QA1
QB7
QB9
B11
Feeder 07-18
IEC16000143-1.en.vsdx
Busbar protection REB670
Application manual