3. Relay settings
3.3. ANSI 25 /A – Automatic Synchronizing
Automatic synchronizing operates when two AC circuits are within the desired limits of frequency, phase angle and voltage range, allowing these two circuits to parallel one another.
There are three automatic synchronizing units. Number 1 is responsible for the synchronization of the feeder bus to bus bar No.1; Number 2, of the feeder bus to bus bar No.2, and Number 3, between bus bar No.1 and bus bar No.2.
The synchronizing units are laid out redundant. Two processor systems are responsible for the control and the supervision of the main breaker-on contact of the synchronizing unit.
If HIMAP is used for ANSI 25 check synchronizing, only the following parameters are required for setup:
Sync. Unit No. 1: 1000…1007 and 1023 Sync. Unit No. 2: 1030…1037 and 1053 Sync. Unit No. 3: 1060…1067 and 1076
HIMAP parameters for Synchronizing Unit 1 (feeder to bus bar1):
Figure: ANSI 25-1 1008. - freq.set.pulse time : 100,0 sec 1009. - freq.set.break time : 2,0 sec
event reminder for output event reminder for output event reminder for output event reminder for output 0 … 9999 mHz
event reminder for output event reminder for output
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HIMAP parameters for Synchronizing Unit 2 (feeder to bus bar2): 1038. - freq.set.pulse time : 100,0 sec 1039. - freq.set.break time : 2,0 sec
1054. – abnormal bus 2 event
BACK EXIT
event reminder for output event reminder for output event reminder for output event reminder for output 0 … 9999 mHz
event reminder for output event reminder for output
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HIMAP parameters for Synchronizing Unit 3 (bus bar1 to bus bar 2): 1068. - freq.set.pulse time : 100,0 sec 1069. - freq.set.break time : 2,0 sec
event reminder for output event reminder for output event reminder for output event reminder for output 0 … 9999 mHz
event reminder for output event reminder for output
!
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The following parameter description corresponds to Synchronizing Unit 1 (feeder to bus bar 1).
Synchronizing Units 2 and 3 have the same parameters and differ only in their parameter and event numbers. (See also description of synchronizing page within the users manual.)
[1000. Sync. Unit 1 active by :]
To activate the Synchronizing Unit No.1, an event number (e.g. binary input event) must be set. If this event number is active, the synchronizing window appears and the synchronizer with its frequency and voltage controller is operative.
[1001. - MAX phase angle :]
The maximum phase angle (positive and negative angle) appears in the window in which the closing order for the switching device (breaker) is given.
[1002. - MAX frequency diff. :]
If the difference of frequency is higher than the set point, then the synchron closing is blocked until the difference of frequency drops below the set point.
[1003. - MIN frequency :]
Minimum frequency limit for “abnormal bus” check. If the frequency of bus bar1 is below the minimum frequency limit, then the frequency controller will be deactivated.
That means the output to send speed lower signals will be blocked.
[1004. - MAX frequency :]
Maximum frequency limit for “abnormal bus” check. If the frequency of bus bar1 is above the maximum frequency limit, then the frequency controller will be deactivated.
That means the output to send speed higher signals will be blocked.
[1005. - MAX voltage diff. :]
If the difference in voltages is higher than the set point, the synchron closing will be blocked until the difference in voltages drops below the set point.
[1006. - MIN voltage :]
Minimum voltage limit for “abnormal bus” check. If the voltage of bus bar1 is below the minimum voltage limit, then the voltage controller will be deactivated. That means the output to send voltage lower signals will be blocked.
[1007. - MAX voltage :]
Maximum voltage limit for “abnormal bus” check. If the voltage of bus bar1 is above the maximum voltage limit, then the voltage controller will be deactivated. That means the output to send voltage higher signals will be blocked.
[1008. - freq.set.pulse time :]
The pulse time for frequency adjustment during synchronization is set here. The pulse time is defined at 100 percent frequency difference. The pulse time, which the frequency controller calculates after the break time, is modified by the difference between the two frequency inputs. The formula for the pulse is:
Calculation for pulse time:
pulse [sec] = Parameter [1008] / 100 * ∆F [%]
Whereby:
Parameter [1008] : pulse time set point at 100% frequency difference.
∆F [%] : frequency difference between feeder and bus bar 1 in percent.
Example: Parameter [1008] = 100sec means:
If the frequency difference between feeder and bus bar 1 is 100%, a pulse of 100 seconds will be set.
If the frequency difference is 1% (0.5Hz at 50Hz nominal-rated frequency), then a pulse of 1 sec will be set, and so on.
[1009. - freq.set.break time :]
The break time between pulse times for speed adjustment during synchronization is set here. After a break time is passed, the frequency controller will calculate the next pulse time to control the pulse event (Event 1008).
[1010. - speed push after 10s :]
If the difference between the electrical angles of the generator and bus bar does not become zero within 10 seconds, then an impulse of the set time in this parameter will be given.
Note: instead of the speed push, the phase regulator can be used.
[1011. - volt.set.pulse time :]
The pulse time for voltage adjustment during synchronization is set here. Pulse time is modified by the difference between the voltages inputs.
[1012. - volt.set.break time :]
The break time between pulse times for voltage adjustment during synchronization is set here.
[1013. - freq. higher event :]
Use this event to activate a digital output in order to increase the frequency during synchronization.
[1014. - freq. lower event :]
Use this event to activate a digital output in order to lower the frequency during synchronization.
[1015. - volt. higher event :]
Use this event to activate a digital output in order to increase the voltage during synchronization.
[1016. - volt. lower event :]
Use this event to activate a digital output in order to lower the voltage during synchronization.
[1017. – phase regu.active at]
The phase regulation can be used to regulate the phase to zero if the two frequencies becomes nearly equal and the phase angle is nearly constant.
If this parameter is set to 0 the phase regulator will be always inactive. Otherwise, if this parameter is set to a value > 0, the speed push (P1010) will be always inactive, and the phase regulator will be activated in the following way:
if the difference between the two frequencies reaches this low limit (P1017), the phase regulator becomes active. The regulator will remain active until the difference exceeds the
“MAX frequency diff.” (P1002).
[1018. – phase 360 deg pulse ]
The pulse time for phase regulation is set here. The pulse time, which the phase regulator calculates after the break time (P1009), is modified by the actual phase angle. The formula for the pulse is: pulse [sec] = (Parameter [1018] * deg) / 360.
[1019. - closing direction :]
The main breaker closing command will be given only when the engine speed is higher (UP), lower (DOWN) or in both directions. See also figure 25-5 and 25-6.
[1020. - CB closing delay :]
The main breaker closing delay is the mechanical delay time caused by the closing time of contactors, relays and the main breaker itself. This delay time can reduce the time period of “breaker synchron on command” Event 1023).
[1021. - live/dead cond. check :]
ON/OFF-switch for dead condition check. If the synchronizing unit recognizes one side (feeder or bus bar) without voltage (dead system), then the Event 1023 (CB sync.ON) will be activated without checking synchronization.
Note: if HIMAP- XG/BCG is selected, only the bus bar will be checked for live/dead condition.
[1022. - min. voltage level :]
If the live/dead condition check (Event 1021) is active and the voltage of one side (feeder or bus bar) is below this voltage limit, the synchronizing unit recognizes dead condition.
[1023. - CB sync. ON event ]
Use this event to send the main breaker close signal. This event will be set if the pointer of the synchronization unit is within the synchron window and the synchronization unit is not blocked.
[1024. - abnormal bus 1 event ]
Use this event to indicate bus abnormal situation. If during synchronization the main conditions for voltage and frequency are not fulfilled for the bus bar, then bus abnormal event will be set and the corresponding controller for voltage and frequency will be blocked. (See Parameters 1003, 1004, 1006, 1007).
The following diagram shows the conditions that have to be fulfilled during synchronizing to set the “CB synchron event” (Event 1023). The parameter and event numbers correspond to Synchronizing Unit 1 (feeder to bus bar 1).
Main condition for MB ON command
SYNCHR. UNIT 1 ON
Parameter [1000]
UBus 1 > UMIN Parameter [1006]
UBus 1 < UMIN Parameter [1007]
FBus 1 > FMIN Parameter [1003]
FBus 1 < FMIN Parameter [1004]
&
≥1
UBus 1 -feed
< Parameter [1005]
UBus 1 -feed
< Parameter [1002]
&
act. Phase angle within synchr. window
Parameter [1001]
Freq. Ctrl. ON Volt. Ctrl. ON
MB close command Event [1023]
abnormal bus Event [1024]
Figure: ANSI 25-4
Note: in the case that the voltages of both systems are “alive” and one system has negative sequence, the synchronizer will be internally blocked, and event 2949 gets active (use this event for an alarm). If both systems have negative sequence the synchronizing process is not blocked.
The following diagrams shows the closing direction philosophy. If closing direction “down”
(Parameter 1019) is selected and if the feeder frequency is higher then the bus bar frequency, then the main breaker synchron close command will be given.
Frequency
actual Bus frequency
t closing direction: DOWN
[Parameter 1019]
CB ON-command
no CB on command
CB ON-command
CB: Circuit breaker HIMAP LC – display:
Feeder frequency
Synchronizing window
For closing direction: DOWN the cursor has to move in the shown direction (F feeder > F bus)
Figure: ANSI 25-5
If closing direction “up” (Parameter 1019) is selected and if the feeder frequency is lower then the bus bar frequency, then the main breaker synchron close command will be given, as the diagram below shows.
Frequency
actual Bus frequency
t closing direction: UP
[Parameter 1019]
CB ON-command
no CB ON command
CB ON-command
CB: Circuit breaker HIMAP LC – display:
Feeder frequency
Synchronizing window
For closing direction: UP the cursor has to move in the shown direction (F feeder < F bus)
Figure: ANSI 25-5