ABB HiPerGuard MV UPS User Manual page 30

3.2.7.3.3. Demand to absorb power into the battery
If the DRC requests the MV UPS to absorb power into the battery, the system will charge the battery
while ensuring that the output voltage stays at its nominal level. The DRC must supervise and manage
the SOC of the battery. Power can only be absorbed when charging capacity in the battery is available.
Figure 3.12: MV UPS power flow – Demand to absorb power into the battery
3.2.7.4. Power Exchanger functionality and parallel units
When MV UPS units are connected in hard-parallel to make a single system, as each unit has its separate
battery, each unit requires a Power Exchanger interface.
It is recommended that the Demand Response control system shall separately monitor the SOC of each
unit and adjust its respective references accordingly.
3.2.8. Auxiliary power supply
The auxiliary power supply of the MV UPS during Power Conditioning and Independent modes of
operation is generated internally. However, an external auxiliary power supply must be available during
the commissioning and servicing for the start of the MV UPS.
This is required for powering the system controller, precharging the DC bus, and controlling the MV
switchgear. For specifications on the auxiliary power supply requirements, please refer to the
Installation Manual.
HI PE RG UA RD M V UP S U S E R M A N UA L
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