Research on coordinated control strategy of an autonomous DC microgrid based on SOC droop control

被引：0
|
作者：
Zhang L. [1 ]
Yan K. [1 ]
Leng X. [2 ]
Lü L. [1 ]
Cai G. [1 ]
机构：
[1] School of Power Engineering, Northeast Electric Power University, Jilin
[2] China Southern Power Grid Energy Development Research Institute Company Limited, Guangzhou
来源：
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | 2021年 / 49卷 / 12期
基金：
中国国家自然科学基金;
关键词：
Coordinated control; DC bus voltage; DC microgrid; Power index droop control; State-of-charge; Voltage feedforward compensation;
D O I：
10.19783/j.cnki.pspc.200734
中图分类号：
学科分类号：
摘要：
As a key component of the autonomous DC microgrid, the Energy Storage System (ESS) is mainly composed of multiple Energy Storage Units (ESUs). There is a problem in that the State-Of-Charge (SOC) equalization speed of multiple ESUs is slow, and a large bus voltage deviation will be generated during the SOC equalization process. Here we propose an improved SOC droop control strategy. First, the control strategy determines the optimal droop curve according to the charging and discharging state of each Energy Storage Unit (ESU) and the SOC value, distributes the load power reasonably, and reduces the bus voltage deviation. Then, by determining the main energy storage unit for power redistribution, and dynamically adjusting the droop coefficient within the allowable range, the system quickly converges to an equilibrium state, and the bus voltage deviation generated by this process is reduced. In addition, when the ESS is out of operation, the photovoltaic system stabilizes bus voltage, and the photovoltaic system is switched from variable step MPPT control to droop control with feedforward compensation to ensure bus voltage stability and safe operation of the microgrid. Finally, the simulation results in Matlab software indicate that the proposed control strategy can reduce the bus voltage deviation and maintain the stable operation of the autonomous DC microgrid while ensuring the rapid equilibrium of the SOC. © 2021 Power System Protection and Control Press.
引用
收藏
页码：87 / 97
页数：10
相关论文
共 25 条
  • [1] XU Xiaoning, ZHOU Xuesong, Control strategy for smooth transfer between grid-connected and island operation for micro grid, High Voltage Engineering, 44, 8, pp. 2754-2760, (2018)
  • [2] BADAL F R, DAS P, SARKER S K, Et al., A survey on control issues in renewable energy integration and microgrid, Protection and Control of Modern Power Systems, 4, 1, pp. 87-113, (2019)
  • [3] LOTFI H, KHODAEI A., AC versus DC microgrid planning, IEEE Transactions on Smart Grid, 8, 1, pp. 296-304, (2017)
  • [4] DUAN J, WANG C, XU H, Et al., Distributed control of inverter-interfaced microgrids based on consensus algorithm with improved transient performance, IEEE Transactions on Smart Grid, 10, 2, pp. 1301-1312, (2019)
  • [5] LI Xialin, GUO Li, WANG Chengshan, Et al., Key technologies of DC microgrids: an overview, Proceedings of the CSEE, 36, 1, pp. 2-17, (2016)
  • [6] WANG Chengshan, LI Wei, WANG Yifeng, Et al., DC bus voltage fluctuation classification and restraint methods review for DC microgrid, Proceedings of the CSEE, 37, 1, pp. 84-98, (2017)
  • [7] WU Qingfeng, SUN Xiaofeng, WANG Yanan, Et al., A distributed control strategy for SOC balancing of distributed energy storage systems in microgrid, Transactions of China Electrotechnical Society, 33, 6, pp. 1247-1256, (2018)
  • [8] MI Yang, JI Hongpeng, HE Xingtang, Et al., Adaptive hierarchical coordinated control of multi-energy storage in isolated DC microgrid, Proceedings of the CSEE, 38, 7, pp. 1980-1989, (2018)
  • [9] HUANG W, ABU Q J., Energy sharing control scheme for state-of-charge balancing of distributed battery energy storage system, IEEE Transactions on Industrial Electronics, 62, 5, pp. 2764-2776, (2015)
  • [10] MI Yang, CAI Hangyi, YUAN Minghan, Et al., Dynamic distribution method of current load for distributed energy storage system in DC microgrid, Electric Power Automation Equipment, 39, 10, pp. 17-23, (2019)
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