Line Differential Protection L4Cpdif; Possible Configurations - ABB RELION 670 Series Application Manual

Section 4
Analog and binary signal transfer for line differential protection
4.6.2
4.6.2.1
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IEC15000451 V2 EN-US
Figure 29: One three–winding transformer in the protected zone

Line differential protection L4CPDIF

Possible configurations

The simplest and most common configuration is the protection of a conventional
two-end power line (see Figure 30). Circuit breakers (CBs) at both ends can be
included in the protected zone depending on their positions relative to the current
transformers (CTs).
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IEC05000039 V3 EN-US
Figure 30: Two-end power line with one CB and one CT group at each end
It is also possible to protect a two-end power line that has two CB and CT groups
at one end and one CB and CT group at the other end (see Figure 31). All currents
from the three CTs must be fed separately to L4CPDIF which processes the
measured currents independently from each other. Summing up the CTs' secondary
currents at the end with two CB and CT groups is not allowed. CBs at both ends
can be included in the protected zone depending on their positions relative to the
CTs.
Protected zone
Protected zone
Communication channel
Communication set-up 670/650 series 2.2
1MRK 505 382-UEN B
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IEC15000451-2-en.vsdx
GUID-566BF5F0-3E2D-42D8-9D53-BCAFB7F0BEA9 v2
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IEC05000039-3-en.vsd
Application Guide