ABB RELION REF615R, Техническое руководство

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Faulted
phases
Used fault
current
Used
polarizing
voltage
Angle difference
A - B I
A
- I
B
V1
ANGLE A V I I
A B
RCA
_ ( ) ( )
= − − − +
ϕ ϕ ϕ
1 30
o
GUID-D510F5F5-D43B-4D35-8963-CDFA325D8036-ANSI V1 EN
B - C I
B
- I
C
V1
ANGLE B V I I
B C
RCA
_ ( ) ( )
= − − − −
ϕ ϕ ϕ
1 90
o
GUID-59B67A43-4CE8-45F6-9D2F-F7177CDC7605-ANSI V1 EN
C - A I
C
- I
A
V1
ANGLE C V I I
C A RCA
_ ( ) ( )
= − − − +
ϕ ϕ ϕ
1 150
o
GUID-FD2EB060-2CB9-49FE-96A8-4E10384AFF95-ANSI V1 EN
V
A
V
B
V
C
I
A
I
B
I
C
V
A
V
B
V
C
I
A
I
B
I
C
A
B
-I
C
I
B
- I
c
-90°
V
1
V
1
GUID-75629DC6-2382-4B00-AB14-1A37836DE736-ANSI V2 EN
Figure 73: Phasors in a single-phase ground fault, phase A to ground, and a two-
phase short circuit, phases B-C, are short-circuited when the polarizing
quantity is the positive-sequence voltage V
1
Network rotation direction
Typically, the network rotating direction is counter-clockwise and defined as "ABC". If
the network rotating direction is reversed, meaning clockwise, that is, "ACB", the
equations for calculating the angle difference needs to be changed. The network rotating
direction is defined with a system parameter
Phase rotation . The change in the network
rotating direction affects the phase-to-phase voltages polarization method where the
calculated angle difference needs to be rotated 180 degrees. Also, when the sequence
components are used, which are, the positive sequence voltage or negative sequence
voltage components, the calculation of the components are affected but the angle
difference calculation remains the same. When the phase-to-ground voltages are used as
the polarizing method, the network rotating direction change has no effect on the direction
calculation.
Section 4
1MRS240050-IB C
Protection functions
150 REF615R
Technical Manual