US 12,348,029 B2
Auxiliary power supply for energy storage systems
Mohsen Asoodar, Solna (SE); Lexuan Meng, Västerås (SE); Tong Wu, Västerås (SE); Jean-Philippe Hasler, Västerås (SE); and Gunnar Ingeström, Västerås (SE)
Assigned to Hitachi Energy Ltd, Zürich (CH)
Appl. No. 18/867,154
Filed by Hitachi Energy Ltd, Zürich (CH)
PCT Filed Jun. 2, 2022, PCT No. PCT/EP2022/065119
§ 371(c)(1), (2) Date Nov. 19, 2024,
PCT Pub. No. WO2023/232260, PCT Pub. Date Dec. 7, 2023.
Prior Publication US 2025/0175030 A1, May 29, 2025
Int. Cl. H02J 11/00 (2006.01); H02J 50/10 (2016.01)
CPC H02J 11/00 (2013.01) [H02J 50/10 (2016.02)] 11 Claims
OG exemplary drawing
 
1. An energy storage system (ESS), comprising:
an energy storage circuit comprising a string of interconnected energy storage units configured to store electrical energy and provide power to a power grid using said stored electrical energy;
an auxiliary module configured to provide auxiliary functions for at least one of the plurality of energy storage units; and
an auxiliary power supply circuit for providing power to the auxiliary module from a grounded power source;
wherein the auxiliary power supply circuit is configured to galvanically isolate the energy storage circuit from the grounded power source,
wherein:
the auxiliary power supply circuit comprises a primary unit, a primary circuit, a secondary unit, and a secondary circuit;
the primary circuit is connected to the energy storage circuit and galvanically isolated from the grounded power source by the primary unit; and
the secondary circuit is connected to the auxiliary module and galvanically isolated from the primary circuit by the secondary unit, and
wherein:
the primary unit comprises a transmitter configured to inject a power signal into the energy storage circuit; and
the secondary unit comprises a receiver configured to receive the power signal from the energy storage circuit and convert the received power signal into power for the auxiliary module.