ABB REG670 2.0 IEC Commissioning Manual page 130

Section 12
Testing functionality by secondary injection
124
If the rated secondary current I
current test I is
ts
I I 4 I 4 A
≤ = × =
ts ovrl rs
EQUATION14041 V1 EN
If the CT of the generator has ratio 9000/1 A, then in primary values
I
rp
I I I 4
≤ = × = ×
t ovrl p , ovrl
I
rs
EQUATION14042 V1 EN
Reference is made to the numerical values of the example, explained in the "Setting
guidelines" of the Application Manual. A test current equal to 2.5 time the base current
of the generator is chosen; this choice is related to the selected test voltage that is
applied while testing the point SE and RE.
I 2 5 . I 2 5 8367 20918 .
= × = ×
t Base
EQUATION14043 V1 EN
The parameter ReachZ1 defines the boundary between zone 1 and zone 2; it is
expressed in percent of the parameter ForwardX. If the setting of ReachZ1 = 12%,
then corresponding primary value of the reactance is
ReachZ 1 ForwardX
X
= ×
RZ 1
100 100
EQUATION14044 V1 EN
The calculation of the test voltage, that is related to ReachZ1, is based on the
impedance Z that has imaginary part X
RZ1
Re achZ 1 ForwardR
RRZ 1
= ×
100 100
EQUATION14045 V1 EN
The magnitude of the impedance Z
= 2 + 2 =
Z R X
RZ 1 RZ 1 RZ 1
EQUATION14046 V1 EN
Hence the reference voltage of the test of the boundary between zone 1 and zone 2 is
V Z I 0 069 20918 1435 .
= × = ×
t RZ , 1 RZ 1 t
EQUATION14047 V1 EN
If the test voltage is lower than V
zone 1; if the test voltage is higher than V
Considering the resistances and reactances which are related to the settings
(ForwardR, ForwardX) and (ReverseR, ReverseX):
of the analog channel is 1 A, then the maximum
rs
9000
36000 A
=
1
A
=
12 59 33 .
ZBase
× = ×
100 100
and real part R
RZ1
12 8 19 .
ZBase
× = ×
100 100
is:
RZ1
2 + 2 = W
0.009 0.068 0.069
V
=
(or in opposition), then the test is related to the
t,RZ1
, then the test is related to the zone 2.
t,RZ1
1MRK502053-UEN B
0 9522 0 . .0 0 68Ω
× =
:
RZ1
0 9522 0 0 . . 0 0 9Ω
× =
Generator protection REG670 2.0 IEC
Commissioning manual
(Equation 1)
(Equation 2)
(Equation 3)
(Equation 4)
(Equation 5)
(Equation 6)
(Equation 7)