IG-150-EN version 04; 03/10/16
70
Protection functions. Description and settings
General instructions
ekor.rps
4.6.11. Neutral directional (67N); I*cos (φ)/I*sen (φ) directional
An input (“67N Isen (
j
) or Icos (
j
)”) can be programmed
and when it gets activated the I*cos (
j
) operation mode
changes to I*sen (
j
). This input, if programmed, cancels the
setting: If it is deactivated the algorithm I*cos (
j
) is carried
out and if it is activated, the I*sen (
j
), regardless the setting.
It does not affect the watimetrical directional or the angular.
I*cos (φ) directional
In order to allow the pick up of the directional unit, the
following must be fulfilled:
1. Exceed the V
n
minimum threshold.
2. The minimum current I
minimum
= I
r
•cos (
j
-
j
c
) must exceed
the minimum threshold in absolute value. If the sign is
negative, the fault is forward. If it is positive, it is reverse.
3. For forwards faults, the angle between the current and
the voltage, displaced the maximum torque angle, and
must be between 97 and 263.
97 < ang (I
0
) – ángle (V
0
) + characteristic angle < 263
4. For backwards faults, the angle between the current
and the voltage, displaced the maximum torque angle,
and must be between 277 and 83.
277 < ang (I
0
) - angle (V
0
) + characteristic angle < 83
The trip zone depends on the angle between the zero
sequence voltage and the zero sequence current. If we are in
the trip zone, the directional gives trip permission when the
Io•cos (
j
-
j
c) value exceeds the setting (in negative value).
I·cos
(
v – i –
φ
)
=
(
Re(V)
⋅
cos(
φ
) + Im(V)
⋅
sin(
φ
)
)
⋅
Re(I) +
(
Im(V)
⋅
cos(
φ
) – Re(V)
⋅
sin(
φ
)
)
⋅
Im(I)
│V│
1
Tripping zone
2
Locking zone
Figure 4.11.
I*cos (φ) directional
Summary of Contents for ekor.rps
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