GE Multilin g60, Instruction Manual

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5-174 G60 Generator Protection System GE Multilin
5.6 GROUPED ELEMENTS 5 SETTINGS
5
• POWER SWING SEAL-IN DELAY: The out-of-step trip FlexLogic operand (
POWER SWING TRIP
) is sealed-in for the
specified period of time. The sealing-in is crucial in the delayed trip mode, as the original trip signal is a very short
pulse occurring when the impedance locus leaves the outer characteristic after the out-of-step sequence is completed.
• POWER SWING TRIP MODE: Selection of the “Early” trip mode results in an instantaneous trip after the last step in
the out-of-step tripping sequence is completed. The early trip mode will stress the circuit breakers as the currents at
that moment are high (the electromotive forces of the two equivalent systems are approximately 180° apart). Selection
of the “Delayed” trip mode results in a trip at the moment when the impedance locus leaves the outer characteristic.
delayed trip mode will relax the operating conditions for the breakers as the currents at that moment are low. The
selection should be made considering the capability of the breakers in the system.
• POWER SWING BLK: This setting specifies the FlexLogic operand used for blocking the out-of-step function only. The
power swing blocking function is operational all the time as long as the element is enabled. The blocking signal resets
the output
POWER SWING TRIP
operand but does not stop the out-of-step tripping sequence.
Figure 5–77: POWER SWING DETECT SCHEME LOGIC (1 of 3)
Figure 5–78: POWER SWING DETECT SCHEME LOGIC (2 of 3)
FLEXLOGIC OPERAND
FLEXLOGIC OPERAND
FLEXLOGIC OPERAND
SETTINGS
SETTING
SETTING
SETTING
POWER SWING QUAD
FWD REACH OUT:
POWER SWING QUAD REV
REACH OUT:
POWER SWING OUTER
LIMIT ANGLE:
POWER SWING MIDDLE
LIMIT ANGLE:
POWER SWING INNER
LIMIT ANGLE:
OUTER IMPEDANCE
REGION
I_1 > PICKUP
MIDDLE IMPEDANCE
REGION
INNER IMPEDANCE
REGION
RUN
RUN
RUN
RUN
POWER SWING REV
REACH: POWER SWING MIDDLE
RGT BLD:
POWER SWING INNER
RGT BLD:
POWER SWING
SHAPE:
POWER SWING OUTER
RGT BLD:
POWER SWING FWD
REACH:
POWER SWING
SUPV:
POWER SWING REV
RCA:
POWER SWING QUAD
FWD REACH MID:
POWER SWING QUAD REV
REACH MID: POWER SWING MIDDLE
LFT BLD:
POWER SWING INNER
LFT BLD:
POWER SWING FWD
RCA: POWER SWING OUTER
LFT BLD:
POWER SWING
FUNCTION:
POWER SWING SOURCE:
Enabled = 1
V_1
I_1
POWER SWING OUTER
POWER SWING MIDDLE
POWER SWING INNER
827840A4.CDR
AND
AND
AND
842008A2.CDR
SETTING
POWER SWING SOURCE:
I_0
I_1
I_2
| |I_0| - |I_0'|| > K_0
SETTING
POWER SWING FUNCTION:
Enabled = 1
| |I_1| - |I_1'|| > K_1
| |I_2| - |I_2'|| > K_2
RUN
OR
I_0, I_1, I_2 - present values
I_0', I_1', I_2' - half-a-cycle old values
K_0, K_2 - three times the average change over last power cycle
K_1 - four times the average change over last power cycle
AND
0
4 cycles
TIMER
0
10 cycles
TIMER
FLEXLOGIC OPERAND
POWER SWING 50DD