Wattmetric-Based Earth-Fault Protection Wpwde (Ansi 32N) - ABB RELION REX640 Technical Manual

1MRS759142 F
4.2.6.10 Technical data
Table 592: HAEFPTOC Technical data
Characteristic
Operation accuracy
Start time ,
Reset time
Reset ratio
Operate time accuracy in definite time mode
Operate time accuracy in IDMT mode
Suppression of harmonics
4.2.7 Wattmetric-based earth-fault protection WPWDE (ANSI
32N)
4.2.7.1 Identification
Function description
Wattmetric-based earth-fault pro-
tection
4.2.7.2 Function block
Figure 304: Function block
4.2.7.3 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.
1
Fundamental frequency current = 1.0 × I
fault current 2.0 ×
2
Includes the delay of the signal output contact.
3
Start time of the function also included.
4 Start value = 2.5 × I
Maximum
REX640
Technical Manual
3
n
Start value , results based on statistical distribution of 1000 measurements.
Start value multiples in range of 2...20.
,
n
Value
Depending on the frequency of the measured current: f
±5% of the set value or ±0.004 × I
Typically 77 ms
Typically 40 ms
Typically 0.96
±1.0% of the set value or ±20 ms
±5.0% of the set value or ±20 ms
-50 dB at f = f
n
-3 dB at f = 13 × f
n
IEC 61850
identification
WPWDE
, harmonics current before fault = 0.0 × I
Protection functions
n
IEC 60617 ANSI/IEEE C37.2
identification device number
Po> -> 32N
, harmonics
n
±2 Hz
n
529