Table of Contents
Advertisement
Line differential protection, phase segregated
(DIFL)
Figure 15:
Operating characteristic
I
I
I
=
+
Diff
Local
Remote
I
I
+
Local
Remote
I
------------------------------------------ -
=
Bias
2
(
)
{
[
(
I
=
Max
I
Bias
Bias
Evaluate
The communication delay is continuously measured and automatically compensated for, in the
differential measurement. This function enables the terminal to use a communication network
with automatic route switching (route switching is frequently used in public digital networks).
The communication telegram is checked for errors, and on detection of erroneous information
the telegram is excluded from the evaluation. In order to trip, two or three out of four accepted
telegrams are required. This provides the needed security against wrong operation due to trans-
mission disturbances.
)
] OR
[
⋅
(
0.5
I
Bias
Own phase
Line differential protection
)
]
}
Other phases
Chapter 4
57
Advertisement
Table of Contents
