ABB 615 series Technical Manual page 822

Section 5
Protection related functions
816
Table 712: Positive-sequence impedance values for typical 11 kV conductors, "Flat" tower
configuration assumed
Name
ACSR 50 SQ.mm
ACSR 500 SQ.mm
Table 713: Positive-sequence impedance values for typical 10/20 kV conductors, "Flat" tower
configuration assumed
Name
Al/Fe 36/6 Sparrow
Al/Fe 54/9 Raven
Al/Fe 85/14 Pigeon
Al/Fe 93/39 Imatra
Al/Fe 108/23 Vaasa
Al/Fe 305/39 Duck
Table 714: Positive-sequence impedance values for typical 33 kV conductors, "Flat" tower
configuration assumed
Name
ACSR 50 sq.mm
ACSR 100 sq.mm
ACSR 500 sq.mm
Zero-sequence impedance values
Location of ground faults requires both positive-sequence and zero-sequence
impedances. For short circuit faults, zero-sequence impedances are not required.
The positive-sequence impedance per unit values for the lines are typically known or can
easily be obtained from data sheets. The zero-sequence values are generally not as easy to
obtain as they depend on the actual installation conditions and configurations. Sufficient
accuracy can, however, be obtained with rather simple calculations using the following
equations, which apply per phase for symmetrically transposed three-phase aluminium
overhead lines without ground wires.
[ 50 ] 1 0 14804 . [ /
R Hz R
≈ + Ω
0
GUID-087D1F51-4C8C-4CF4-ACE5-9F43AF0DD3FC V1 EN
R1 [Ω/km]
0.532
0.0725
R1 [Ω/km]
0.915
0.578
0.364
0.335
0.287
0.103
R1 [Ω/km]
0.529
0.394
0.0548
]
km
1MAC059074-MB A
X1 [Ω/km]
0.373
0.270
X1 [Ω/km]
0.383
0.368
0.354
0.344
0.344
0.314
X1 [Ω/km]
0.444
0.434
0.346
(Equation 152)
615 series ANSI
Technical Manual