Stabilized And Instantaneous Differential Protection For Two- Or Three-Winding Transformers Tr3Ptdf (Ansi 87T3) - ABB RELION REX640 Technical Manual

Protection functions
4.3.2.11 Technical data
Table 663: TR2PTDF Technical data
Characteristic
Operation accuracy
Start time
Reset time
Reset ratio
Suppression of harmonics
4.3.3 Stabilized and instantaneous differential protection for
two- or three-winding transformers TR3PTDF (ANSI 87T3)
4.3.3.1 Identification
Function description
Stabilized and instantaneous differ-
ential protection for two- or three-
winding transformers
4.3.3.2 Function block
Figure 405: Function block
4.3.3.3 Functionality
The stabilized and instantaneous differential protection for two- or three-winding
transformers function TR3PTDF provides up to three three-phase current sets
or restraints designed for the protection of two-winding or three-winding
transformers and generator-transformer blocks. It is possible to have two three-
1
Current before fault = 0.0 × l
2
Measured with static power output f
716
1, 2
Low stage
High stage
, f = 50 Hz. Injected differential current = 2.0 × set operation value
n n
= 50 Hz.
n
Value
Depending on the frequency of the measured current:
f ±2 Hz
n
±3.0% of the set value or ±0.002 × I
Minimum Typical
31 ms 35 ms
15 ms 17 ms
Typically 40 ms
Typically 0.96
DFT: -50 dB at f = n × f , where n = 2, 3, 4, 5, ...
n
IEC 61850 IEC 60617
identification identification
TR3PTDF 3dI>3W
1MRS759142 F
n
Maximum
40 ms
20 ms
ANSI/IEEE C37.2
device number
87T3
REX640
Technical Manual