ABB RELION Series Technical Manual page 627

1MRS758755 A
REC615 and RER615
Technical Manual
the closing signal is given until the circuit breaker finally closes is about 50...250 ms.
The selected Closing time of CB informs the function how long the conditions have to
persist. The Synchro check function compensates for the measured slip frequency and
the circuit breaker closing delay. The phase angle advance is calculated continuously
with the formula.
Closing angle = ∠ U
(
Bus
GUID-48292FC2-C00C-4166-BCAD-FFC77D7F196B V1 EN
∠ U Measured bus voltage phase angle
Bus
∠U Measured line voltage phase angle
Line
f Measured bus frequency
Bus
f Measured line frequency
line
T Total circuit breaker closing delay, including the delay of the protection relay output contacts
CB
Closing time of CB setting parameter value
defined with the
The closing angle is the estimated angle difference after the breaker closing delay.
The Minimum Syn time setting time can be set, if required, to demand the minimum
time within which conditions must be simultaneously fulfilled before the SYNC_OK
output is activated.
The measured voltage, frequency and phase angle difference values between the two
sides of the circuit breaker are available as monitored data values U_DIFF_MEAS,
FR_DIFF_MEAS and PH_DIFF_MEAS. Also, the indications of the conditions that
are not fulfilled and thus preventing the breaker closing permission are available as
monitored data values U_DIFF_SYNC, PH_DIF_SYNC and FR_DIFF_SYNC.
These monitored data values are updated only when the Synchro check is enabled with
the Synchro check mode setting and the measured ENERG_STATE is "Both Live".
Continuous mode
The continuous mode is activated by setting the parameter Control mode to
"Continuous". In the continuous control mode, Synchro check is continuously
checking the synchronism. When synchronism is detected (according to the settings),
the SYNC_OK output is set to TRUE (logic '1') and it stays TRUE as long as the
conditions are fulfilled. The command input is ignored in the continuous control
mode. The mode is used for situations where Synchro check only gives the permission
to the control block that executes the CB closing.
U f f
) ( (
− ∠ ° + −
Line Bus line
Section 9
Control functions
T T
) ( ) 360 )
× + × °
CB PL
(Equation 74)
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