ABB RELION Series Technical Manual page 493

1MRS758755 A
REC615 and RER615
Technical Manual
GUID-134928BF-ACE3-42C9-A70F-985A1913FB75 V3 EN
Figure 251: Description of the equivalent load distance
The exact value for Equivalent load Dis can be calculated based on the load flow and
voltage drop calculations using data from DMS-system and the following equation.
Equivalent load Dis
GUID-E447E8AC-65F7-4586-B853-C297347303FF V2 EN
U The actual maximum voltage drop of the feeder
d(real)
U The fictional voltage drop, if the entire load would be tapped at the end (d=1) of the
d(tap,d=1)
feeder (not drawn in
the DMS system.
Alternatively, the setting Equivalent load Dis can be determined by conducting a
single-phase earth-fault test (R
maximum actual voltage drop takes place. This point is typically located at the end of
the main line. As a result, the calculated value is stored in the recorded data Equivalent
load Dis.
In addition, when the setting EF algorithm Sel is equal to "Load modelling", the EF
algorithm Cur Sel setting determines whether zero-sequence "Io based" or negative-
sequence "I2 based" current based algorithm is used. The difference between "Io
Protection related functions
U
d real ( )
=
U
d tap d ( , ) 1
=
Figure 251). The calculation of this value requires data from
= 0 Ω) at that point of the feeder where the
fault
Section 5
(Equation 50)
487