US 11,685,289 B2
Charging and discharging device, methods of battery charging and discharging, and charging and discharging system
Jinfeng Gao, Ningde (CN); Chen Qi, Ningde (CN); Xiyang Zuo, Ningde (CN); and Xiaojian Huang, Ningde (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed on Dec. 27, 2021, as Appl. No. 17/562,286.
Application 17/562,286 is a continuation of application No. PCT/CN2021/109379, filed on Jul. 29, 2021.
Prior Publication US 2023/0035744 A1, Feb. 2, 2023
Int. Cl. B60L 58/12 (2019.01); B60L 50/64 (2019.01); H02J 7/00 (2006.01)
CPC B60L 58/12 (2019.02) [B60L 50/64 (2019.02); H02J 7/007 (2013.01); B60L 2210/10 (2013.01); B60L 2210/30 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A charging and discharging device, comprising an alternating current/direct current (AC/DC) converter, a first direct current/direct current (DC/DC) converter, a second DC/DC converter and a control unit, wherein one end of the second DC/DC converter is connected between the first DC/DC converter and the AC/DC converter and the other end of the second DC/DC converter is connected to an energy storage unit; and
the control unit is configured to:
receive a first charging request transmitted by a battery management system (BMS) of a battery, the first charging request comprising a first charging voltage and a first charging current,
set output power of the first DC/DC converter as first output power of the first DC/DC converter based on the first charging voltage and the first charging current,
acquire a state of charge (SOC) of the energy storage unit,
turn on the second DC/DC converter under the condition that the SOC of the energy storage unit is greater than a first threshold, to charge the battery by the energy storage unit through the first DC/DC converter and the second DC/DC converter,
acquire a bus voltage of the charging and discharging device in real time, and
adjust output power of the second DC/DC converter to the first output power of the second DC/DC converter under the condition that the battery is charged by the energy storage unit, the bus voltage is less than a bus balance voltage and a difference between the bus voltage and the bus balance voltage exceeds a preset value, the first output power of the second DC/DC converter being less than or equal to a maximum output power of the second DC/DC converter,
wherein the difference between the bus voltage and the bus balance voltage is less than or equal to the preset value after the output power of the second DC/DC converter is adjusted to the first output power of the second DC/DC converter.