Connection Of Analog Currents - ABB REC670 Applications Manual

Section 17
Monitoring
17.8.3.1
542
in the observed bay (no parallel line expected since chosen input is set to zero). Use the
Parameter Setting tool within PCM600 for changing analog configuration.
The measured phase voltages can be fine tuned with the parameters VAGain, VBGain
and VCGain to further increase the accuracy of the fault locator.
The list of parameters explains the meaning of the abbreviations. Figure
presents these system parameters graphically. Note, that all impedance values relate to
their primary values and to the total length of the protected line.
R +jX
1A 1A
DRPRDRE
LMBRFLO
ANSI05000045 V2 EN-US
Figure 213: Simplified network configuration with network data, required for
settings of the fault location-measuring function
For a single-circuit line (no parallel line), the figures for mutual zero-sequence
impedance (X , R ) and analog input are set at zero.
0M 0M
Power system specific parameter settings are not general settings but specific setting
included in the setting groups, that is, this makes it possible to change conditions for
the Fault locator with short notice by changing setting group.
The source impedance is not constant in the network. However, this has a minor
influence on the accuracy of the distance-to-fault calculation, because only the phase
angle of the distribution factor has an influence on the accuracy. The phase angle of the
distribution factor is normally very low and practically constant, because the positive
sequence line impedance, which has an angle close to 90°, dominates it. Always set the
source impedance resistance to values other than zero. If the actual values are not
known, the values that correspond to the source impedance characteristic angle of 85°
give satisfactory results.

Connection of analog currents

Connection diagram for analog currents included IN from parallel line shown in figure
214.
R +jX
0L 0L
R +jX
1L 1L
Z =Z +jX
0m 0m 0m
R +jX
0L 0L
R +jX
1L 1L
ANSI05000045_2_en.vsd
1MRK 511 401-UUS A
213
R +jX
1B 1B
Bay control REC670 2.2 ANSI
Application manual
also
M13769-16 v5