8.2.7
Operation principle
The Four step phase overcurrent protection OC4PTOC is divided into four different
sub-functions, one for each step. For each step
x
, where x is step 1, 2, 3 and 4, an
operation mode is set by
DirModex
:
Off
/
Non-directional
/
Forward
/
Reverse
.
The protection design can be divided in four parts:
•
The direction element
•
The harmonic Restraint Blocking function
•
The four step over current function
•
The mode selection
If VT inputs are not available or not connected, setting parameter
DirModex
shall be left to default value,
Non-directional
.
en05000740-2-en.vsd
Direction
Element
4 step over current
element
One element for each
step
Harmonic
Restraint
Mode Selection
dirPh1Flt
dirPh2Flt
dirPh3Flt
harmRestrBlock
enableDir
enableStep1-4
DirectionalMode1-4
faultState
Element
faultState
I3P
U3P
START
TRIP
IEC05000740 V2 EN
Figure 158:
Functional overview of OC4PTOC
1MRK502052-UEN B
Section 8
Current protection
345
Technical manual
Summary of Contents for Relion REG670
Page 1: ...Relion 670 series Generator protection REG670 2 0 IEC Technical manual ...
Page 2: ......
Page 44: ...38 ...
Page 58: ...52 ...
Page 80: ...74 ...
Page 106: ...100 ...
Page 482: ...476 ...
Page 548: ...542 ...
Page 570: ...564 ...
Page 600: ...594 ...
Page 608: ...602 ...
Page 630: ...624 ...
Page 862: ...856 ...
Page 1094: ...1088 ...
Page 1226: ...1220 ...
Page 1250: ...1244 ...
Page 1297: ...1291 ...