US 12,149,083 B2
Controller and method for balancing discharge or charge of battery packs in energy storage system
Ratnesh Sharma, Fremont, CA (US); Surinder Singh, Fremont, CA (US); Brandon Ohara, Mountain View, CA (US); Motoko Furukawa, San Jose, CA (US); and Roger Keyes, Mission, KS (US)
Assigned to China Energy Investment Corporation Limited, Beijing (CN); and National Institute of Clean-and-Low-Carbon Energy, Beijing (CN)
Filed by China Energy Investment Corporation Limited, Beijing (CN); and National Institute of Clean-and-Low-Carbon Energy, Beijing (CN)
Filed on Oct. 20, 2021, as Appl. No. 17/506,153.
Prior Publication US 2023/0117104 A1, Apr. 20, 2023
Int. Cl. H02J 7/00 (2006.01); B60L 53/63 (2019.01); B60L 55/00 (2019.01); B60L 58/13 (2019.01); H02J 3/32 (2006.01)
CPC H02J 3/322 (2020.01) [B60L 53/63 (2019.02); B60L 55/00 (2019.02); B60L 58/13 (2019.02); H02J 3/32 (2013.01); H02J 7/0014 (2013.01); H02J 7/0048 (2020.01); H02J 2310/48 (2020.01)] 20 Claims
OG exemplary drawing
 
1. A system, comprising:
a plurality of battery packs;
one or more power converters, each power converter coupled with at least one of the plurality of battery packs and configured to convert direct current (DC) from one battery pack to alternating current (AC) or vice versa; and
a controller coupled to the plurality of battery packs and the one or more power converters, the controller comprising one or more processor and at least one tangible, non-transitory machine readable medium encoded with one or more programs configured to perform steps comprising:
collecting characteristic data of each battery pack including a present voltage (Vi), state of charge (SOCi), a number of cells in each battery packs (Nc), a maximum voltage (Vc max) and a minimum voltage (Vc min) of a cell;
receiving a total power demand (D) needed to be dispatched from the system or to be charged to the system in a first time interval;
assigning a first weighting factor (a) and a second weighting factor (b) for power assignment based on voltage and state of charge of each battery pack, respectively, wherein a+b=1;
determining a respective power discharge or charge for each battery pack based on the present voltage (Vi), the state of charge (SOCi), the number of cells in each battery packs (Nc), the maximum voltage (Vc max) and the minimum voltage (Vc min) of a cell, the first weighting factor (a), the second weighting factor (b), and the total power demand (D); and
providing signals with instructions to the plurality of battery packs and the one or more power converters for discharging power from or charging power to the plurality of battery packs based on the respective power discharge or charge of each battery pack and/or keeping a certain battery pack idle.