α
Lead BusA
f s
TCB ds
dt
TCB
= ⋅ ⋅ +
⋅
⋅
360
2
1000 1000
(Equation 372)
f
BusA
Bus A side frequency
s Frequency slip
ds/dt Frequency slip acceleration
TCB Setting
Closing time of CB
The breaker closes only when the measured phase-angle difference across
the breaker (PH_DIFF_MEAS) equals the calculated lead angle (α
Lead
) and all
synchronization check conditions are fulfilled.
If
Synchrocheck mode
is set to "Synchronous", a zero-passage of the
phase-angle difference is not necessary and CB closing is permitted as
soon as all the synchrocheck conditions are fulfilled. Similarly for dead
bus synchronization, CB closing is possible when the energizing check
permits.
The CB closing signal can be blocked based on the inputs CB_TEST and EXT_CHECK
and IED test mode as described in
Table 1532
. This blocking status is available in the
monitored data CB_CL_BLKD.
Table 1532: CB_CL_BLKD status based on the inputs
IED test mode Inputs Monitored data
CB_TEST EXT_CHECK CB_CL_BLKD
TRUE TRUE TRUE 1 (“Unblocked”)
FALSE FALSE
TRUE TRUE FALSE 2 (“Ext Check Fail”)
FALSE FALSE
TRUE FALSE N/A 3 (“IED Test CB Serv-
ice”)
FALSE TRUE N/A 4 (“IED Service CB
Test”)
ASNSCSYN can be set to the bypass mode by setting the parameters
Synchrocheck
mode
and
Live dead mode
to "Off" or, alternatively, by activating the BYPASS input.
In the bypass mode, the closing conditions are always considered to be fulfilled by
ASNSCSYN.
Synchronization control
The general bus bar arrangement for a non-source CB bus is shown in
Figure
873
. The bus to which the generator is connected is determined based on the
circuit breaker and isolator position inputs (CB_OPEN, CB_CLOSE, ISO_A1_CLOSE,
ISO_A2_CLOSE, ISO_B1_CLOSE and ISO_B2_CLOSE). The generator's bus
connection status is shared with ASCGAPCs as part of the NS_ASC_DATA output.
1MRS759142 F
Control functions
REX640
Technical Manual
1595
To Next Page
Loading...
