The novel multiagent distributed SOC balancing strategy for energy storage system in DC microgrid without droop control. (March 2023)

• Record Type: Journal Article
• Authors: Mi, Yang; Deng, Jin; Yang, Xingwu; Zhao, Yao; Tian, Shuxin; Fu, Yang
• Is Part Of: International journal of electrical power & energy systems. Volume 146(2023)
• Publication Date: 2023-03
• Subjects: Distributed control -- DC microgrids -- Multiagent system -- Dynamic average consensus -- State of charge balancing; Electrical engineering -- Periodicals; Electric power systems -- Periodicals; Électrotechnique -- Périodiques; Réseaux électriques (Énergie) -- Périodiques; Electric power systems; Electrical engineering; Periodicals; 621.3
• DOI: 10.1016/j.ijepes.2022.108716
• Languages: English
• ISSNs: 0142-0615

Abstract

Highlights: A novel distributed control strategy based on multiagent system is proposed to achieve the state of charge (SOC) balancing of the energy storage system (ESS) in the DC microgrid. In the proposed scheme, it does not depend on the output current of the converter. The voltage loop stabilizes the bus voltage, and the current closed loop achieves SOC balancing through reasonable dynamic current distribution. An adaptive current segmentation regulation algorithm is designed to improve the SOC balance speed on the basis of avoiding the circulating current in the ESS, especially when the SOC difference among ESSs is small. The proposed control strategy can improve the current regulation performance in steady state and transient state, and also has favorable voltage control capability and stability. In addition, this scheme uses a dynamic consistency protocol based on multiagent system, which is robust against communication failures and can realize plug-in and plug-out of ESS. The real-time test results basedonthe OPAL-RT platform verify the effectiveness of the proposed control strategy. Abstract: For the distributed energy storage system (ESS) in a DC microgrid, the novel distributed control strategy based on multiagent control is designed to achieve state of charge (SOC) balancing. In the proposed scheme, the output current of the converter is not required, which is an attractive feature to avoid the measurement error. The voltage loop can stabilize the bus voltage and provide the original current reference for each ESS. The SOC information is introduced to design the current closed loop, so that the operating current of the ESS can be dynamically adjusted to realize SOC balance control according to the SOC and capacity of each ESS during the charging and discharging process. Furthermore, in order to avoid the circulating current in ESSs, an adaptive current segment regulation algorithm is designed to improve the SOC balance speed, especially in the case of low SOC difference among ESSs. The proposed control strategy not only can enhance the current regulation performance under steady and transient states, but also has favorable voltage control capability and stability. Finally, the real-time test results in OPAL-RT platform are presented to validate the effectiveness of the proposed method.