GE N60 Instruction Manual page 282

5.6 GROUPED ELEMENTS
5
The power swing detect element provides both power swing blocking and out-of-step tripping functions. The element mea-
sures the positive-sequence apparent impedance and traces its locus with respect to either two or three user-selectable
operating characteristic boundaries. Upon detecting appropriate timing relations, the blocking and tripping indications are
given through FlexLogic operands. The element incorporates an adaptive disturbance detector. This function does not trig-
ger on power swings, but is capable of detecting faster disturbances – faults in particular – that may occur during power
swings. Operation of this dedicated disturbance detector is signaled via the
The power swing detect element asserts two outputs intended for blocking selected protection elements on power swings:
POWER SWING BLOCK
is established in the same way, but resets when an extra disturbance is detected during the power swing.
SWING UN/BLOCK
The
POWER SWING UN/BLOCK
faults during power swing conditions.
Different protection elements respond differently to power swings. If tripping is required for faults during power swing condi-
tions, some elements may be blocked permanently (using the
and dynamically unblocked upon fault detection (using the
View the operating characteristic and logic figures along with the following discussion to develop an understanding of the
operation of the element.
The power swing detect element operates in three-step or two-step mode:
• Three-step operation: The power swing blocking sequence essentially times the passage of the locus of the positive-
sequence impedance between the outer and the middle characteristic boundaries. If the locus enters the outer charac-
teristic (indicated by the
cated by the
POWER SWING MIDDLE
5-164
POWER SWING MIDDLE
MESSAGE
LFT BLD: 100.00 
POWER SWING INNER
MESSAGE
RGT BLD: 100.00 
POWER SWING INNER
MESSAGE
LFT BLD: 100.00 
POWER SWING PICKUP
MESSAGE
DELAY 1: 0.030 s
POWER SWING RESET
MESSAGE
DELAY 1: 0.050 s
POWER SWING PICKUP
MESSAGE
DELAY 2: 0.017 s
POWER SWING PICKUP
MESSAGE
DELAY 3: 0.009 s
POWER SWING PICKUP
MESSAGE
DELAY 4: 0.017 s
POWER SWING SEAL-IN
MESSAGE
DELAY: 0.400 s
POWER SWING TRIP
MESSAGE
MODE: Delayed
POWER SWING BLK:
MESSAGE
Off
POWER SWING
MESSAGE
TARGET: Self-Reset
POWER SWING
MESSAGE
EVENTS: Disabled
is a traditional signal that is safely asserted for the entire duration of the power swing, and
operand may be used for blocking selected protection elements if the intent is to respond to
POWER SWING OUTER
FlexLogic operand) for an interval longer than
N60 Network Stability and Synchrophasor Measurement System
Range: 0.10 to 500.00 ohms in steps of 0.01
Range: 0.10 to 500.00 ohms in steps of 0.01
Range: 0.10 to 500.00 ohms in steps of 0.01
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: Early, Delayed
Range: Flexlogic operand
Range: Self-Reset, Latched, Disabled
Range: Disabled, Enabled
POWER SWING 50DD
POWER SWING BLOCK
POWER SWING UN/BLOCK
FlexLogic operand) but stays outside the middle characteristic (indi-
5 SETTINGS
operand.
operand), and others may be blocked
operand).
POWER SWING PICKUP DELAY 1
GE Multilin
POWER
, the