Considering the resistances and reactances which are related to the settings
(ForwardR
, ForwardX) and (ReverseR, ReverseX):
R
ForwardR
ZBase
FwdR
= × = × =
100
8 19
100
0 9522 0 078
.
. . Ω
EQUATION14048 V1 EN-US (Equation 1
1)
X
ForwardX
ZBase
FwdX
= × = × =
100
59 33
100
0 9522 0 565
.
. . Ω
EQUATION14049 V1 EN-US (Equation 12)
R
ReverseR
ZBase
RvsR
= × = × =
100
0 29
100
0 9522 0 003
.
. . Ω
EQUATION14050 V1 EN-US (Equation 13)
X
ReverseR
ZBase
RvsX
= × = × =
100
29 6
100
0 9522 0 282
.
. . Ω
EQUATION14051 V1 EN-US (Equation 14)
and the voltages that are related to them:
V Z I R X I
t FwdZ FwdZ t FwdR FwdX t,
. . .= × = + × = + × =
2 2 2 2
0 078 0 565 20918 0 5700 20918 11931× = V
EQUATION14052 V1 EN-US (Equation 15)
V Z I R X I
t RvsZ RvsZ t RvsR RvsX t,
. . .= × = + × = + × =
2 2 2 2
0 003 0 282 20918 0 2822 20918 5899× = V
EQUATION14053 V1 EN-US (Equation 16)
The previous calculations are in primary values. They are transferred to secondary
values to perform injections by a test set. Primary values are transferred to
secondary values by taking into account the CT ratio and the VT ratio (respectively
9000/1 A and 13.8/0.1 kV in the example).
The magnitude of the secondary voltages, that are related to the points RE and SE
of the R-X plane, needs to be checked.
RE (R
FwdR
, X
FwdX
):
V V
V
V
V
t FwdZs t FwdZ
VT s
VT p
, ,
,
,
.
.
.= × = × =11931
0 1
13 8
86 45
EQUATION14054 V1 EN-US (Equation 17)
SE (R
RvsR
, X
RvsX
):
V V
V
V
V
t RvsZs t RvsZ
VT s
VT p
, ,
,
,
.
.
.= × = × =5899
0 1
13 8
42 75
EQUATION14055 V1 EN-US (Equation 18)
The tests, which are described in this section, may require voltages that have
magnitude equal to 110% of the previous values. The continuous permissive
overload voltage of the protection voltage channels of the TRM module is 420 V;
so the previous voltages may be applied to the analog channels of the IED
continuously
. Limitations may be related to the available test set; the current I
t
was
Section 11 1MRK 505 378-UEN A
Testing functionality by secondary injection
152 Line differential protection RED670 2.2 IEC
Commissioning manual
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