Section 4 1MAC309294-MB F
Protection functions
112 RER620
Technical Manual
Figure 49: Phasors in a single-phase ground fault, phases A-N, and two-phase
short circuit, phases B and C, when the actuating polarizing quantity is
the negative-sequence voltage -V2
Positive-sequence voltage as polarizing quantity
Table 131: Equations for calculating angle difference for positive-sequence quantity polarizing method
Faulted
phases
Used fault
current
Used
polarizing
voltage
Angle difference
AI
A
V1
BI
B
V1
CI
C
V1
A - B I
A
- I
B
V1
B - C I
B
- I
C
V1
C - A I
C
- I
A
V1
ANGLE A V I
A
RCA
_()()=−−
1
ANGLE B V I
B
RCA
_()()=−−−
1 120
ANGLE C V I
C
RCA
_()()=−−+
1 120
ANGLE A V I I
AB
RCA
_()( )=−−−+
130
ANGLE B V I I
BC
RCA
_()( )=−−−−
190
ANGLE C V I I
CA
RCA
_()( )=−−−+
1 150
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