Operation Principle - ABB REG650 Technical Manual

Section 8
Current protection
8.1.7
faultState
I3P
V3P
I3P
ANSI05000740 V1 EN
Figure 80: Functional overview of OC4PTOC (51/67)
172

Operation principle

The protection design can be decomposed 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
DirModeSelx shall be left to default value, Non-directional.
dirPhAFlt
Direction
Element
dirPhBFlt
dirPhCFlt
Harmonic
harmRestrBlock
Restraint
Element
enableDir
Mode Selection
enableStep1-4
DirectionalMode1-4
The sampled analog phase currents are processed in a pre-processing function block.
Using a parameter setting MeasType within the general settings for the four step phase
1MRK 502 043-UUS B
4 step over current
element
faultState
One element for each
step
en05000740_ansi.vsd
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