ABB RELION REX640 Technical Manual page 645

1MRS759142 C
REX640
Technical Manual
The BLKD5H output is activated when the biased low stage is blocked by the fifth
harmonic blocking functionality. Correspondingly, when the operation of the biased
low stage is blocked by the waveform blocking functionality, the BLKDWAV output is
activated according to the phase information.
When required, the operating outputs of the biased low stage can be blocked by the
external control signals BLK_OPR_LS and BLOCK.
The operation of the protection relay is affected by biasing as shown in
I [%Ir]
d
300
200
100
I
d1
Low operate value
Section 1
End section 1
GUID-66D3973C-7946-4751-B72B-CECA6028F6B1 V1 EN
Figure 352: Operation characteristic for biased operation of TR3PTDF
The Low operate value setting of the biased stage of the differential function is
determined according to the operating characteristics curve:
Low operatevalue Id
1
=
GUID-A0F88921-16EE-40BD-AA41-D88326D6FABF V1 EN
The Slope section 2 setting is determined correspondingly:
Id
2
Slope section 2 =
100 %
⋅
Ib 2
GUID-0C06D5D7-1204-424C-9791-4BA21294CCC1 V1 EN
The second turning point End section 2 can be set in the range 100...500%.
The slope of the operating characteristic curve of the differential function varies in
three different sections of the range.
I
b2
I
d2
100 200
Section 2
End section 2
Section 4
Protection functions
Figure
I
b3
I
d3
300 400 500
Section 3
(Equation 117)
(Equation 118)
352.
I [%Ir]
b
639