ABB COM600 series, User'S & Technical Manual, Page: 29 / 60

Table 4.3-2 Positive-sequence impedance values for typical 10/20 kv conductors,
“Flat” tower configuration assumed
X1 [Ω/km] R1 [Ω/km] Name
0.383 0.915 Al/Fe 36/6 Sparrow
0.368 0.578 Al/Fe 54/9 Raven
0.354 0.364 Al/Fe 85/14 Pigeon
0.344 0.335 Al/Fe 93/39 Imatra
0.344 0.287 Al/Fe 108/23 Vaasa
0.314 0.103 Al/Fe 305/39 Duck
Table 4.3-3 Positive-sequence impedance values for typical 33kv conductors,
“Flat” tower configuration assumed
X1 [Ω/km] R1 [Ω/km] Name
0.444 0.529 ACSR 50 sq.mm
0.434 0.394 ACSR 100 sq.mm
0.346 0.0548 ACSR 500 sq.mm
Positive-sequence impedance values
An accurate fault localization requires good setting values for line impedances. As
datasheet impedance per unit values are valid only for a certain tower configuration, the
values should be adjusted according to the actual installation configuration. This minim-
izes the fault localization errors caused by inaccurate settings.
The positive-sequence reactance per unit and per phase can be calculated with a certain
approximation equation which applies to symmetrically transposed threephase aluminum
overhead lines without ground wires.
equation_15.png
Figure 4.3-24 (Equation 15)
the geometric average of phase distances [m]
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COM600 series 5.1 1MRS758734
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