Patent ID: 11923721
Assignee: SAUDI ARABIAN OIL COMPANY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. One or more non-transitory computer-readable storage media coupled to one or more processors and having instructions stored thereon which, when executed by the one or more processors, cause the one or more processors to perform operations for configuring a Direct Current Uninterruptible Power Supply (DC UPS), the DC UPS comprising an alternating current (AC) input, and the operations comprising:
determining an acceptable voltage for a load to be connected to the DC UPS, wherein the DC UPS comprises a plurality of battery cells;
selecting, based on the acceptable voltage, an intermediate battery cell of the plurality of battery cells, wherein a subset of the plurality of battery cells includes a first battery cell through the intermediate battery cell, and wherein the subset of the plurality of battery cells provides power to the load in a first DC UPS mode;
connecting a first connection path from the intermediate battery cell to an output bus of the DC UPS;
connecting a second connection path from a last battery cell of the plurality of battery cells to the output bus, wherein all of the plurality of battery cells provide power to the load in a second DC UPS mode;
installing a circuit switch along the second connection path, the circuit switch arranged to open or close the second connection path;
installing an undervoltage relay in the output bus; and
setting, based on the acceptable voltage, a threshold voltage of the undervoltage relay that is less than a voltage of the first battery cell through the intermediate battery cell of the subset of the plurality of battery cells when the AC input fails, wherein the undervoltage relay is configured to:
in the first DC UPS mode, control the circuit switch to open the second connection path when the voltage on the output bus exceeds the threshold voltage so that the subset of the plurality of battery cells provides power to the output bus; and
in the second DC UPS mode, control the circuit switch to close the second connection path when the voltage on the output bus drops below the threshold voltage so that all of the plurality of battery cells provide power to the output bus.