ABB 615 series Technical Manual page 815

1MAC059074-MB A
615 series ANSI
Technical Manual
Line length = 1 p.u.
S
S
0 · · · · ·
1
2
Actual load distribution
(Evenly distributed load)
V
drop(real)
0
distance of equivalent load tap = Equivalent load Dis
0
GUID-6325E875-F7DB-4D1B-978A-1E1583EB544C V1 EN
Figure 412: 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-348E8311-D555-4897-BF7E-077024585AAC V1 EN
V The actual maximum voltage drop of the feeder
d(real)
V 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
DMS system.
Alternatively, the setting Equivalent load Dis can be determined by conducting a single-
phase ground-fault test (R
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.
Protection related functions
S
Simplified voltage drop
curve used in algorithm
Actual voltage
drop curve
0.5 1.0
1.0
Ʃ
S
i
V
d real ( )
V
d tap d
( , ) 1
=
Figure 412). The calculation of this value requires data from the
= 0 Ω) at that point of the feeder where the maximum actual
fault
Section 5
n
Line length
(p.u)
(Equation 142)
809