US 12,009,682 B2
Load access detection method, switch circuit, and battery management system
Xu Zhang, Ningde (CN); Hang Ma, Ningde (CN); and Xingchang Wang, Ningde (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Fujian (CN)
Filed on Sep. 20, 2021, as Appl. No. 17/479,505.
Application 17/479,505 is a continuation of application No. PCT/CN2020/133455, filed on Dec. 2, 2020.
Claims priority of application No. 202010274684.X (CN), filed on Apr. 9, 2020.
Prior Publication US 2022/0006308 A1, Jan. 6, 2022
Int. Cl. H02J 7/00 (2006.01); B60L 3/00 (2019.01); B60L 3/12 (2006.01); B60L 58/12 (2019.01); G01R 31/3835 (2019.01); H02J 7/34 (2006.01)
CPC H02J 7/0047 (2013.01) [B60L 3/0046 (2013.01); B60L 3/12 (2013.01); B60L 58/12 (2019.02); G01R 31/3835 (2019.01); H02J 7/007182 (2020.01); H02J 7/345 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A load access detection method, comprising:
detecting a voltage at a first detection point, wherein the first detection point is electrically connected to a positive electrode of a battery group in a battery pack through a bridging resistor;
detecting a voltage at a second detection point, wherein the second detection point is short-circuited with the first detection point when the battery pack is connected to a load circuit; and
under a voltage difference between the voltage at the first detection point and the voltage at the second detection point being less than or equal to a preset voltage threshold condition, controlling a switch circuit to enter a pre-charging mode, and pre-charging a load capacitor in the load circuit through the battery pack, wherein a charging current of the switch circuit in the pre-charging mode is less than a charging current of the switch circuit in a charging mode.