TY - GEN
T1 - A capacitor-isolated balancing circuit for battery modules applied in grid-tied battery energy storage system
AU - Sun, Baiyan
AU - Gao, Congzhe
AU - Chen, Zhen
AU - Cheng, Shuoqi
AU - Sun, Te
N1 - Publisher Copyright:
© 2020 IEEE.
PY - 2020/10/30
Y1 - 2020/10/30
N2 - This paper proposes a capacitor-isolated balancing circuit (CIBC) for battery modules in grid-tied battery energy storage system (BESS). The grid-tied converter in the BESS consists of three star-connected H bridges with lower dc bus voltage compared with three-phase converter. To realize required voltage and power, cells are series connected to form battery modules which are connected in series further to achieve high dc bus voltage and large capacity, thus leading to the fact that the voltage of a module is much higher than that of a cell. To realize the module voltage balance, a novel capacitor-isolated balancing circuit topology is proposed. In this balancing circuit the isolation capacitor withstands the offset dc voltage among battery modules instead of semiconductor switches or transformer. The voltage stress on the semiconductor switch is not higher than a battery module voltage. Besides, zero current switching is achieved in the CIBC, which improves the equalization efficiency. In the CIBC transformer is eliminated and CIBC has good modularity. Furthermore, a frequency varying control based on the model of power and impedance is presented, and the control method is easy and effective for the CIBC. The feasibility of the proposed CIBC for battery modules in BESS is validated through simulations.
AB - This paper proposes a capacitor-isolated balancing circuit (CIBC) for battery modules in grid-tied battery energy storage system (BESS). The grid-tied converter in the BESS consists of three star-connected H bridges with lower dc bus voltage compared with three-phase converter. To realize required voltage and power, cells are series connected to form battery modules which are connected in series further to achieve high dc bus voltage and large capacity, thus leading to the fact that the voltage of a module is much higher than that of a cell. To realize the module voltage balance, a novel capacitor-isolated balancing circuit topology is proposed. In this balancing circuit the isolation capacitor withstands the offset dc voltage among battery modules instead of semiconductor switches or transformer. The voltage stress on the semiconductor switch is not higher than a battery module voltage. Besides, zero current switching is achieved in the CIBC, which improves the equalization efficiency. In the CIBC transformer is eliminated and CIBC has good modularity. Furthermore, a frequency varying control based on the model of power and impedance is presented, and the control method is easy and effective for the CIBC. The feasibility of the proposed CIBC for battery modules in BESS is validated through simulations.
KW - Battery energy storage system
KW - Capacitor-isolated balancing circuit
KW - Zero current switching
UR - http://www.scopus.com/inward/record.url?scp=85101650404&partnerID=8YFLogxK
U2 - 10.1109/EI250167.2020.9346685
DO - 10.1109/EI250167.2020.9346685
M3 - Conference contribution
AN - SCOPUS:85101650404
T3 - 2020 IEEE 4th Conference on Energy Internet and Energy System Integration: Connecting the Grids Towards a Low-Carbon High-Efficiency Energy System, EI2 2020
SP - 2722
EP - 2727
BT - 2020 IEEE 4th Conference on Energy Internet and Energy System Integration
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 4th IEEE Conference on Energy Internet and Energy System Integration, EI2 2020
Y2 - 30 October 2020 through 1 November 2020
ER -
