GE MiCOM P40 Agile Technical Manual page 96

P44x/EN ST/Hb6
(ST) 4-22
Menu text
GROUP 1: POWER SWING
IN > (% Imax)
Residual current threshold for power swing unblocking. It is a percentage of the highest
measured current on any phase.
– Typical setting: 40%
– Minimum setting (to avoid maloperation for asymmetric in power swing currents): > 30%
– Maximum setting (to ensure unblocking for line faults): < 100%
I2 > Status
Negative Sequence current power swing unblocking criteria activation:
Enables or disables the phase-phase fault protection during Power Swing Blocking. When
enabled, the relay will trip when I
I2 > (% Imax)
Negative Sequence current threshold for power swing unblocking. It is a percentage of the
highest measured current on any phase.
– Typical setting: 30%
– Minimum setting (to avoid maloperation for asymmetric in power swing currents): > 10%
– Maximum setting (to ensure unblocking for line faults): < 50%
Imax line > Status
Phase current power swing unblocking criteria activation:
Enables or disables the three-phase fault protection during Power Swing Blocking. When
enabled, the relay will trip when phase current threeshold exceeds Imax line >.
Imax line >
Phase current threshold for power swing unblocking (unit:A)
– Minimum setting: 1.2 × [ maximum power swing current ]
– Maximum setting: 0.8 × [ minimum phase fault current level ]
Delta I Status
Delta I criterion status activation:
Enables or disables the unblocking logic three-phase fault protection during Power Swing
Blocking. Time delay is settable.
Unblocking Time delay
Time-delay after which blocking criteria is automatically removed. Typical setting:
– 30s if a near permanent block is required,
– 2s if unblocking is required to split the system.
Blocking Zones
Allow zone blocking in case of a power swing.
The Blocked Zones function bits are set to 1 to block zone tripping or are set to 0 to allow
tripping as normal.
When the criteria for power swing detection are met (3 single phase loop inside the quad &
crossing the ∆R band in less than 5 ms in a 50 Hz network), and when out of step tripping is
selected, then the distance protection with all of its stages is blocked – to prevent tripping by
the distance protection (the relay can operate normally for any fault occurring during a
power swing as there are different criteria which can be used by monitoring current & delta
current).
Out of Step
Threshold of number of out of steps. Triggers DDB #352 when reached.
Setting of the number of steps to confirm Out Of Step (OOS) condition.
Default setting
40% 10%
Enabled Disabled or Enabled
> 'I2 > (% Imax)' or when I
2
30% 10%
Enabled Disabled or Enabled
3 x In 1 x In
Enabled Disabled or Enabled
30s 0
00000000 Bit 0: Z1/Z1X Block, Bit 1: Z2 Block,
Bit 2: Zp Block, Bit 3: Zq Block, Bit 4: Z3
Block, Bit 5: Z4 Block
1 1
MiCOM P40 Agile P442, P444
Setting range
Min Max
100%
< 0.1 × In.
2
100%
20 x In
30s
255
Setting
Step size
1%
1%
0.01 x In
0.1s
1