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 BUS1; Number 2, of the feeder BUS to BUS2, and Number 3, between BUS1 and BUS2.
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.
NOTE: About the calibration parameters [0042] to [0044] you can put the respective
synchronizing units 1 to 3 properly. On this occasion, the phase corner is calibrated to neutralise the phase displacement. However, the calibration can occur only about the parametertool (see Parametertool, chapter 2.4.4).
If SYMAP® is used for ANSI 25 check synchronizing only the following parameters are required for setup:
• Sync. Unit No. 1: [1000] to [1007] and [1023]
• Sync. Unit No. 2: [1030] to [1037] and [1053]
• Sync. Unit No. 3: [1060] to [1067] and [1076]
SYMAP® parameters for Synchronizing Unit 1 (feeder to BUS1) (figures 3-10 and 3-11):
Figure 3-10 ANSI 25/A-1
ANSI 25 /A Synchronizing relay 1000. Sync. unit 1 active by : 0 1001. - MAX phase angle : 8 deg 1002. - MAX frequency diff. : 150 mHz 1003. - MIN frequency : 99.0 % 1004. - MAX frequency : 101.0 % 1005. - MAX voltage diff. : 5.0 % 1006. - MIN voltage : 95.0 % 1007. - MAX voltage : 105.0 % 1008. - freq.set.pulse time : 100.0 sec 1009. - freq.set.break time : 2.0 sec 1010. – speed push after 10s : 500 ms 1011. – volt.set.pulse time : 180.0 sec
↓ BACK EXIT
Setting range:
Event no.
0-30 deg 0-2000 mHz 70.0-100.0 % 100.0-130.0 % 0.1-30.0 % 70.0-100.0 % 100.0-130.0 % 0.1-999.9 sec 0.1-999.9 sec 0-9999 ms 0.1-999.9 sec
Service Manual
Figure 3-11 ANSI 25/A-2
SYMAP® parameters for Synchronizing Unit 2 (feeder to BUS2) (figures 3-12 and 3-13):
Figure 3-12 ANSI 25/A-3
ANSI 25 /A Synchronizing relay
↑ 1038. - freq.set.pulse time : 100.0 sec 1039. - freq.set.break time : 2.0 sec ANSI 25 /A Synchronizing relay
↑
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
* must be smaller than parameter [1002]
Figure 3-13 ANSI 25/A-4
SYMAP® parameters for Synchronizing Unit 3 (BUS1 to BUS 2) (figures 3-14 and 3-15):
Figure 3-14 ANSI 25/A-5
ANSI 25 /A Synchronizing relay
↑ 1068. - freq.set.pulse time : 100.0 sec 1069. - freq.set.break time : 2.0 sec ANSI 25 /A Synchronizing relay
↑
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 BACK EXIT
Service Manual
Figure 3-15 ANSI 25/A-6
Parameter description:
The following parameter descriptions correspond to Synchronizing Unit 1 (feeder to BUS1).
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 user’s 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. If the Synchronizing Unit is active then the Synchronizing Site is indicated (see also chapter 2.4.4.8 in User’s Manual).
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 BUS1 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 BUS1 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.
ANSI 25 /A Synchronizing relay
↑
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 BACK EXIT
1006. - MIN voltage :
Minimum voltage limit for “abnormal BUS” check; if the voltage of BUS1 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 BUS1 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 characteristic for frequency adjustment during synchronization is set here. This time defines the pulse time which corresponds to 100% frequency difference. The calc.
pulse is modified by the difference between the two frequency inputs in the following way:
Calc. pulse (sec) = Parameter [1008] / 100 × ΔF (%)
with:
Parameter [1008] : defined pulse time at 100% frequency difference,
ΔF (%): frequency difference between FEEDER and BUS1 in percent of nominal
Example: Typical Setting: 100 sec
Parameter [1008] = 100 sec means:
If the frequency difference between FEEDER and BUS1 is 100% a calc. pulse of 100 seconds will be set.
If the frequency difference is 0.5 Hz (1% at 50 Hz nominal-rated frequency) then a calc. pulse of 1 sec will be set.
If the frequency difference is positive (FFEEDER > FBUS1) the n < event [1014] will be activated for the calc. pulse time.
If the frequency difference is negative (FFEEDER < FBUS1) the n > event [1013] will be activated for the calc. pulse time.
1009. - freq.set.break time :
Typical setting: 2 sec
The cycle time for the calculation of the pulse times for speed adjustment during
synchronization is set here. At the beginning of the break time, the frequency controller will calculate and set the next pulse (see parameter [1008]).
1010. - speed push after 10 s :
If the difference between the electrical angles of the generator and BUS 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.
Service Manual
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 become 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 (parameter [1010]) 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 (parameter [1017]), the phase regulator becomes active. The phase regulator remains active so long the difference is under the limit of the “MAX of frequencies diff.” (Parameters [1002]) then the frequency regulator becomes again active (parameters [1017] < parameters [1002]).
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 (parameter [1009]), 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 3-13 and 3-14).
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) below the voltage limit of parameter [1022] (dead system) and the other side within the voltage limits parameters [1006] and [1007] and the frequency limits parameters [1003] and [1004] (live system), then the event [1023] (CB sync.ON) will be activated without checking synchronization.
NOTE: If Device type - XG/BCG is selected and sync. unit 1 or 2 is active only the BUS will be checked for 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) 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 BUS1 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 then BUS abnormal event will be set and the corresponding controller for voltage and frequency will be blocked (see parameters [1003], [1004], [1006] and [1007]).
Figure 3-16 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 BUS1).
Figure 3-16 ANSI 25/A-7
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.
Main condition for „MB ON” command
&
SYNCHR. UNIT 1 ON Parameter [1000]
UBUS1 > UMIN
Parameter [1006]
UBUS1 < UMAX Parameter [1007]
FBUS1 > FMIN Parameter [1003]
FBUS1 < FMAX Parameter [1004]
≥ 1
Freq. Ctrl. release Freq. Ctrl. release
abnormal BUS Event [1024]
&
│act. Phase angle│
< Parameter [1001]
│UBUS1-UFeeder│
< Parameter [1002]
│UBUS1-UFeeder│
< Parameter [1005]
MB close command (here Parameter [1029] „both“
Event [1023]
Service Manual The figures 3-13 and 3-14 show the closing direction philosophy. If closing direction “UP”
(parameter [1019]) is selected and if the feeder frequency is higher than the BUS frequency then the main breaker synchron close command will be given (see figure 3-17).
Figure 3-17 ANSI 25 /A-8
If closing direction “DOWN” (parameter [1019]) is selected and if the feeder frequency is lower than the BUS frequency then the main breaker synchron close command will be given (see figure 3-18).
Figure 3-18 ANSI 25 /A-9 FBus
Fmax; Para [1004]
Fmin; Para
Time Frequency
Closing direction: „DOWN“
(FFeeder > FBus)
Phase angle Cursor direction: to the right
1: No “C. B. ON” Command
2: “C. B. ON” Command,allowed if Phase synchron and voltage O.K.
FFeeder
2 2
2 1 1 1
1
Synchronizing window Synchronizing window
FBus
Fmax; Para [1004]
2 1 2 1 2 1 2 Time
1
Fmin; Para [1003]
Para [1004]
Frequency
1: No “C. B. ON” Command
2: “C. B. ON” Command,allowed if Phase synchron and voltage O.K.
FFeeder
Closing direction: „UP“
(FFeeder < FBUS)
Phase angle Cursor direction: to the left