ABB RED650 User Manual

Section 6 Differential protection
6.1 Line differential protection
IP13934-1 v1
6.1.1 Identification
M14844-1 v4
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Line differential protection 3 CT sets,
with in-zone transformers, 2-3 line ends
LT3CPDIF
3Id/I>
SYMBOL-HH V1 EN-US
87LT
Line differential logic LDLPSCH - 87L
6.1.2 Functionality
6.1.2.1 Line differential protection for 3 CT sets, 2-3 line ends, in-zone
transformer LT3CPDIF
M14932-3 v9
One three-winding power transformer can be included in the line differential
protection zone. In such application, the differential protection is based on the
ampere turns balance between the transformer windings. Three-winding
transformers are correctly represented with vector group compensations made in
the algorithm. The function includes 2
nd
and 5
th
harmonic restraint and zero-
sequence current elimination. The phase-segregated differential protection with
single-pole tripping is usually not possible in such applications.
IED
IED IED
Protected zone
Comm. Channel
Comm. Channel
Comm. Channel
IEC05000042_2_en.vsd
IEC05000042 V2 EN-US
Figure 30: Example of application on a three-terminal line with an in-line
power transformer in the protection zone
1MRK 505 394-UEN A Section 6
Differential protection
Line differential protection RED650 2.2 IEC 85
Technical manual

ABB RED650 Specifications

General

Brand	ABB
Model	RED650
Category	Protection Device
Language	English