ABB RELION Series - Page 239

In an example case of a two-phase short-circuit failure where the fault is between
phases B and C, the angle difference is measured between the polarizing quantity U
BC
and operating quantity I
B
- I
C
in the self-polarizing method.
GUID-65CFEC0E-0367-44FB-A116-057DD29FEB79 V1 EN
Figure 126: Two-phase short circuit, short circuit is between phases B and C
Cross-polarizing as polarizing quantity
Table 242: Equations for calculating angle difference for cross-polarizing method
Faulte
d
phase
s
Used
fault
current
Used
polarizing
voltage
Angle difference
A I
A
U
BC
ANGLE A U I
BC
A
RCA
o
_ ( ) - ( ) - = + ϕ ϕ ϕ 90
GUID-4F0D1491-3679-4B1F-99F7-3704BC15EF9D V3 EN
B
I
B
U
CA
ANGLE B U I
CA
B
RCA
o
_ ( ) - ( ) - = + ϕ ϕ ϕ 90
GUID-F5252292-E132-41A7-9F6D-C2A3958EE6AD V3 EN
C
I
C
U
AB
ANGLE C U I
AB
C
RCA
o
_ ( ) - ( ) - = + ϕ ϕ ϕ 90
GUID-84D97257-BAEC-4264-9D93-EC2DF853EAE1 V3 EN
A - B
I
A
- I
B
U
BC
-
U
CA
ANGLE A U U I I
BC CA
A B
RCA
o
_ ( - ) - ( - ) - = + ϕ ϕ ϕ 90
GUID-AFB15C3F-B9BB-47A2-80E9-796AA1165409 V2 EN
B - C I
B
- I
C
U
CA
-
U
AB
ANGLE B U U I I
CA AB
B C
RCA
o
_ ( - ) - ( - ) - = + ϕ ϕ ϕ 90
GUID-C698D9CA-9139-40F2-9097-007B6B14D053 V2 EN
C - A I
C
- I
A
U
AB
-
U
BC
ANGLE C U U I I
AB BC
C A
RCA
o
_ ( - ) - ( - ) - = + ϕ ϕ ϕ 90
GUID-838ECE7D-8B1C-466F-8166-E8FE16D28AAD V2 EN
The angle difference between the polarizing quantity U
BC
and operating quantity I
A
is
marked as φ in an example of the phasors in a single-phase earth fault where the
1MRS758755 A Section 4
Protection functions
REC615 and RER615 233
Technical Manual