Toshiba GR 200 Series, Инструкция по эксплуатации

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6F2S1915 (0.46)
GRZ200 (Soft 031 & 032)
- 323 -
As shown in Figure 2.23-1, a single IED is located near Bus G. When a fault (F) occurs
on the line GH, the fault distance (GF) is calculated in percent using the following equation.
Fault distance (%) =
Distance to fault F
Length of Line GH
× 100
(2.23-9)
(iii)
Fault information
Detailed information is displayed along with the distance to the fault (see Figure 2.23-2.c). The
output of the FL information is simplified by means of notations; these are summarized in
Table 2.23-2.
Table 2.23-2 Notation of fault information on screen
Fault info.
notation
Meaning Comment
OB Outside boundary
The FL function determines a fault location as being
outside of the boundary. The boundary is defined with
setting [
FL_Line_km
] or [
FL_Line_mile
].
NC No convergence†
If a number of computation results are scattered, the
FL function will select one of the resulting values from
where the scattering is minimal.
†Note: The FL function can determine the convergence in the computation when the
difference between the maximum value and the minimum value is less than 0.2
km. For the convergence decision, the values are calculated three times: a value
calculated for the current samples, a value three samples prior to the current
samples and a value six samples prior to the current samples. (2.66.2)
2.23.3
Setting and operation
To run the FL function, the user must provide several setting items: the direction for which
the fault location is required, the mode selection for impedance settings, the impedances† of
the local and adjacent lines, imbalance-impedances and compensation factors, distance-unit
for the FL function, and others.
†Note: For impedance settings, the user should convert the primary values to secondary
values with regard to the line VT and CT. Set impedances as total-impedances; do
not set impedances as impedance per distance-unit.
(i)
Impedance setting using symmetrical components
Provided the self-impedances and the mutual-impedances are symmetrically balanced (that is,