ABB RELION Series, Техническое руководство

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Characteristic Value
Operate time accuracy in definite time mode ±1.0% of the set value or ±20 ms
Operate time accuracy in IDMT mode
3)
±5.0% of the set value or ±20 ms
Suppression of harmonics -50 dB at f = f
n
-3 dB at f = 13 × f
n
1) Fundamental frequency current = 1.0 × I
n
, harmonics current before fault = 0.0 × I
n
, harmonics fault
current 2.0 × Start value, results based on statistical distribution of 1000 measurements
2) Includes the delay of the signal output contact
3) Maximum Start value = 2.5 × I
n
, Start value multiples in range of 2...20
4.2.6 Wattmetric-based earth-fault protection WPWDE
4.2.6.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Wattmetric-based earth-fault protection WPWDE Po> -> 32N
4.2.6.2 Function block
GUID-EDE21448-13FD-44E3-AF7C-CFD47A5C99DC V1 EN
Figure 187: Function block
4.2.6.3 Functionality
The wattmetric-based earth-fault protection function WPWDE can be used to detect
earth faults in unearthed networks, compensated networks (Petersen coil-earthed
networks) or networks with a high-impedance earthing. It can be used as an alternative
solution to the traditional residual current-based earth-fault protection functions, for
example, the IoCos mode in the directional earth-fault protection function
DEFxPDEF.
WPWDE measures the earth-fault power 3UoIoCosφ and gives an operating signal
when the residual current Io, residual voltage Uo and the earth-fault power exceed the
set limits and the angle (φ) between the residual current and the residual voltage is
inside the set operating sector, that is, forward or backward sector. The operating time
characteristic can be selected to be either definite time (DT) or a special wattmetric-
type inverse definite minimum type (wattmetric type IDMT).
The wattmetric-based earth-fault protection is very sensitive to current transformer
errors and it is recommended that a core balance CT is used for measuring the residual
current.
Section 4
1MRS758755 A
Protection functions
360 REC615 and RER615
Technical Manual