ABB REG670 Commissioning Manual page 169

1MRK 502 073-UUS A
Generator protection REG670 2.2 ANSI and Injection equipment REX060, REX061, REX062
Commissioning manual
and the voltages that are related to them:
2
V Z I R
= × =
t FwdZ , FwdZ t FwdR
EQUATION14052 V1 EN-US
2
V Z I R
= × = +
t RvsZ , RvsZ t RvsR
EQUATION14053 V1 EN-US
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 , X ):
FwdR FwdX
V
VT s ,
V V
11931
= × =
t FwdZs t FwdZ
, ,
V
VT p ,
EQUATION14054 V1 EN-US
SE (R , X ):
RvsR RvsX
V
VT s ,
V V 5899
= × =
t RvsZs , t RvsZ ,
V
VT p
,
EQUATION14055 V1 EN-US
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
using a factor 2.5 (instead of the maximum value 4) in order to reduce the magnitude
of the test voltage for the points RE and SE.
Test sets usually do not have a feature to simulate a real network during a power swing
and apply the related analog quantities at the terminal of the generator. The scope of
the present test is not a simulation of a real network. Voltages and currents are supplied
in order to measure an impedance that changes in the time and traverses the plane R-X
and, in particular, the area inside the lens characteristic. The test may be performed by
applying:
• Symmetric three-phase voltage at 50 Hz. The magnitude depends on the point of
the characteristic that needs to be verified. The following three main points of the
line segment SE-RE need to be checked:
Testing functionality by secondary injection
2 2
X I 0 078 . 0 565 .
+ × = +
FwdX t
2 2
X I
0 003 . 0 282 .
× = +
RvsX t
0 1 .
V
86 45 .
× =
13 8 .
0 1 .
42 75 . V
× =
13 8 .
Section 13
2
20918 0 570 0 20918 11931 .
× = × =
2
20918 0 282 2 20918 5899 .
× = × =
was calculated by
t
V
(Equation 12)
V
(Equation 13)
(Equation 14)
(Equation 15)
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