GE Multilin g60 Instruction Manual page 305

5 SETTINGS
• POWER SWING SEAL-IN DELAY: The out-of-step trip FlexLogic™ operand (
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
SETTING
POWER SWING
FUNCTION:
Disabled = 0
Enabled = 1
SETTING
POWER SWING SOURCE:
V_1
_1
Figure 5–65: POWER SWING DETECT SCHEME LOGIC (1 of 3)
SETTING
POWER SWING FUNCTION:
Disabled = 0
Enabled = 1
SETTING
POWER SWING SOURCE:
I_0
I_1
I_2
Figure 5–66: POWER SWING DETECT SCHEME LOGIC (2 of 3)
GE Multilin
operand but does not stop the out-of-step tripping sequence.
SETTINGS
POWER SWING POWER SWING OUTER
SHAPE: LIMIT ANGLE:
POWER SWING FWD POWER SWING MIDDLE
REACH: LIMIT ANGLE:
POWER SWING QUAD POWER SWING INNER
FWD REACH MID: LIMIT ANGLE:
POWER SWING QUAD POWER SWING OUTER
FWD REACH OUT: RGT BLD:
POWER SWING FWD POWER SWING OUTER
RCA: LFT BLD:
POWER SWING REV POWER SWING MIDDLE
REACH: RGT BLD:
POWER SWING QUAD REV POWER SWING MIDDLE
REACH MID: LFT BLD:
POWER SWING QUAD REV POWER SWING INNER
REACH OUT: RGT BLD:
POWER SWING REV POWER SWING INNER
RCA: LFT BLD:
RUN
OUTER IMPEDANCE
REGION
RUN
MIDDLE IMPEDANCE
REGION
RUN
INNER IMPEDANCE
REGION
SETTING
POWER SWING
SUPV:
RUN
_1 > PICKUP
RUN
| |I_0| - |I_0'|| > K_0
| |I_1| - |I_1'|| > K_1
| |I_2| - |I_2'|| > K_2
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
G60 Generator Protection System
5.6 GROUPED ELEMENTS
POWER SWING TRIP
FLEXLOGIC OPERAND
AND POWER SWING OUTER
FLEXLOGIC OPERAND
AND POWER SWING MIDDLE
FLEXLOGIC OPERAND
AND POWER SWING INNER
827840A3.CDR
TIMER
0
10 cycles
TIMER
FLEXLOGIC OPERAND
0
POWER SWING 50DD
4 cycles
) is sealed-in for the
5
842008A1.CDR
5-145