ABB HiPerGuard MV UPS User Manual page 73

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8.1.1 System states
8.1.1.1 Bypass Isolate state
When system control is powered up, the HiPerGuard MV UPS transits to non-operational "Bypass isolate" state:
• MV input breaker(s) (Sin), output circuit breaker (s) (Sout) both open.
• MV bypass circuit breaker (Sabp) closes.
• MV UPS(s) is (are) not running.
8.1.1.2 Starting state
When a START request is received, the HiPerGuard MV UPS transits to "Starting state":
• HiPerGuard MV UPS(s) output voltage is synchronized to grid input voltage.
• MV input breaker(s) (Sin), output circuit breaker(s) (Sout) both close.
• MV bypass circuit breaker (Sabp) opens.
HiPerGuard MV UPS system is now in "Running state".
8.1.1.3 Running state
When in "Running state" and grid input voltage is within thresholds, HiPerGuard MV UPS(s) transit(s) to the "PCM_
Normal state":
• HiPerGuard MV UPS(s) regulates output voltage to nominal settings.
• HiPerGuard MV UPS(s) phase locks output frequency to grid frequency.
• Utility grid supplies the load's active power requirements.
The HiPerGuard MV UPS(s) remain(s) in this state until a power quality event is detected.
8.1.1.4 PCM_Active state
When a power quality event is detected, and the grid voltage is out of threshold, the HiPerGuard MV UPS(s) tran-
sit(s) to "PCM_Active state".
• The HiPerGuard MV UPS(s) will attempt to ride through the event if it is a shallow surge or sag event.
• If during the event, the grid voltage goes outside the Sin input breaker(s) management curves, then the
HiPerGuard MV UPS(s) commands (all) Sin to open.
• After (all) Sin open(s), HiPerGuard MV UPS(s) transit(s) to "Island state" inside the Independent mode
(IM).
8.1.1.5 Island state
While in "Island state" the HiPerGuard MV UPS(s) fully support(s) the load from the energy storage system and
continues to monitor for the return of grid voltage.
8.1.1.6 Resynchronizing State
When the grid input voltage recovers and stabilizes within the specified thresholds:
• HiPerGuard MV UPS(s) transit(s) to "Resynchronizing state" and the output voltage(s) is (are) phase
locked to the grid input voltage.
• When synchronization has been achieved, the HiPerGuard MV UPS(s) command(s) circuit breaker(s) Sin
to close, and transits to "PCM_Normal state".
If a power quality event occurs while HiPerGuard MV UPS(s) is (are) in "Resynchronizing state", then the MV UPS(s)
will transit back to "Island state".
8.1.1.7 Stopping state
When in "Running state" and a STOP command or Fault trip occurs:
HiPerGuard MV UPS(s) transit(s) to "Stopping state".
• MV input breaker (Sin), output circuit breaker (Sout) both open.
• MV bypass circuit breaker (Sabp) closes.
• MV UPS is now in "Bypass isolate state".