Toshiba GR 200 Series, Инструкция по эксплуатации

Страница: 345 / 1563

6F2S1915 (0.46)
GRZ200 (Soft 031 & 032)
- 324 -
Z
aa
=Z
bb
=Z
cc
and Z
ab
=Z
bc
=Z
ca
), then symmetrical setting is applicable. If the impedance
unbalances cannot be ignored, the user shall set a compensation factor (section (i)-4) or use a
matrix setting (section (ii)).The following equations are used to acquire the zero-sequence and
positive-sequence impedances.
Z
1
=
Z
aa
+ Z
bb
+ Z
cc
− (Z
ab
+Z
bc
+ Z
ca
)
3
(2.23-10)
Z
0
=
Z
aa
+ Z
bb
+ Z
cc
+ 2(Z
ab
+ Z
bc
+ Z
ca
)
3
(2.23-11)
where,
Z1
: Positive-sequence series-impedance
Z0
: Zero-sequence series-impedance
Zaa, Zbb, Zcc
: Self-impedances for each phase conductor
Zab, Zbc, Zca
: Mutual-impedances between phases
Selection of symmetrical setting mode
Prior to setting, the user should set the scheme switch [
FL_ImpSet
] to
Symmetrical
.
Setting zero-sequence impedance
With regard to the zero-sequence-impedance (Z0GH), the user should set the value of
resistance for setting [
FL_R0
] and the value of reactance for setting [
FL_X0
]. (See
Figure 2.23-1)
Setting positive-sequence impedance
With regard to the positive-sequence-impedance (Z1GH), the user should set the value
of resistance for setting [
FL_R1
] and the value of reactance for setting [
FL_X1
]. (See
Figure 2.23-1)
Setting compensation factors
Set 100% for the settings when the impedance unbalances can be ignored in each of
phases. If the self- and mutual-impedances are unbalanced, then the user should adjust
the FL results using compensation factors expressed using Equations (2.23-12) to
(2.23-17) below. The user can set the values of the compensation factors using settings
[
FL_Kab
] to [
FL_Kc
] in the symmetrical setting mode.