Abstract In order to settle the energy balancing issue between energy storage modules and improve the modularity of the cascade storage energy storage system, this paper proposes a distributed energy balancing control strategy. Independent voltage and current closed loops are built in the strategy by making full use of the DC converter modular structure characteristics. For the purpose of making sub-modules balance energy independently, droop control ideology and state of charge (SOC) are adopted in the redesigned current loop. Thus, the sub-module can adjust the operating current according to its SOC, and then realize the automatic adjustment of energy distribution to achieve the purpose of balancing control. In order to reduce the effect of SOC on system current, current correction unit is introduced to improve the current regulation. This strategy has no influence on the ability of ESS to stabilize the DC bus voltage and does not require any communication between modules, so that the system owns complete modular features. At last, the experimental results have verified the proposed strategy.
Bi Kaitao,Sun Li,An Quntao等. Distributed Energy Balancing Control Strategy for Energy Storage System Based on Modular Multilevel DC-DC Converter[J]. Transactions of China Electrotechnical Society, 2018, 33(16): 3811-3821.
[1] 夏欢, 杨中平, 杨志鸿, 等. 基于列车运行状态的城轨超级电容储能装置控制策略[J]. 电工技术学报, 2017, 32(21): 16-23. Xia Huan, Yang Zhongping, Yang Zhihong, et al.Control strategy of supercapacitor energy storage system for urban rail transit based on operating status of trains[J]. Transactions of China Electrotechnical Society, 2017, 32(21): 16-23. [2] 李武华, 徐驰, 禹红斌, 等. 直流微网系统中混合储能分频协调控制策略[J]. 电工技术学报, 2016, 31(14): 84-92. Li Wuhua, Xu Chi, Yu Hongbin, et al.Frequency dividing coordinated control strategy for hybrid energy storage system of DC micro-grid[J]. Transactions of China Electrotechnical Society, 2016, 31(14): 84-92. [3] 顾帅, 韦莉, 张逸成, 等. 超级电容器不一致性研究现状及展望[J]. 中国电机工程学报, 2015, 35(11): 2862-2869. Gu Shai, Wei Li, Zhang Yicheng, et al.Review of no uniformity research and analysis on supercapacitor[J]. Proceedings of the CSEE, 2015, 35(11): 2862-2869. [4] Cao J, Schofield N, Emadi A.Battery balancing methods: a comprehensive review[C]//2008 IEEE Vehicle Power and Propulsion Conference, Hangzhou, China, 2008: 1-6. [5] Linzen D, Buller S, Karden E.Analysis and evaluation of charge balancing circuits on perfor- mance reliability and lifetime of supercapacitor systems[J]. IEEE Transactions on Industry Appli- cations, 2005, 41(5): 1135-1141. [6] Pascual C, Krein P T.Switched capacitor system for automatic series battery equalization[C]//Proceedings of 12th IEEE Applied Power Electronics Conference, Charlotte, North Carolina, 1997: 439-446. [7] Yuanmao Y, Cheng K W E, Yeung Y P B, Zero- current switching switched capacitor zero voltage gap automatic equalization system for series battery strings[J]. IEEE Transactions on Power Electronic, 2012, 27(7): 3234-3242. [8] 许爱国, 谢少军, 刘小宝. 串联电容器动态电压均衡技术研究[J]. 中国电机工程学报, 2010, 30(12): 111-116. Xu Aiguo, Xie Shaojun, Liu Xiaobao.Dynamic voltage equalization technique for series connected ultra-capacitors[J]. Proceedings of the CSEE, 2010, 30(12): 111-116. [9] Li S, Mi C C, Zhang M.A high-efficiency active battery balancing circuit using multi-winding trans- former[J]. IEEE Transactions on Industry Appli- cations, 2013, 49(1): 198-207. [10] Chen Yang, Liu Xiaofang, Cui Yangyi.A multi- winding transformer cell-to-cell active equalization method for lithium-ion batteries with reduced number of driving circuits[J]. IEEE Transactions on Power Electronic, 2016, 31(7): 4916-4929. [11] 胡斌, 杨中平, 黄先进, 等. 用于超级电容储能系统的三电平双向直流变换器及其控制[J]. 电工技术学报, 2015, 30(8): 83-89. Hu Bin, Yang Zhongping, Huang Xianjin, et al.Three-level bi-directional DC-DC converter and its control strategy used for supercapacitor Energy storage system[J]. Transactions of China Electro- technical Society, 2015, 30(8): 83-89. [12] Huang W, Qahouq J A.Energy sharing control scheme for state-of-charge balancing of distributed battery energy storage system[J]. Transactions on Industrial Electronics, 2015, 62(5): 2764-2776. [13] Ota J I Y, Sato T, Akagi H. Enhancement of performance, availability, and flexibility of a battery ESS based on a modular multilevel cascaded converter (MMCC-SSBC)[J]. IEEE Transactions on Industrial Electronics, 2016, 63(31): 2791-2799. [14] Seong-Chon Choi, Jin-Yong Jeon, Tae-Jung Yeo.State-of-charge balancing control of a battery power module for a modularized battery for electric vehicle[J]. Journal of Electrical Engineering and Technology, 2016, 11(3): 629-638. [15] 武伟, 谢少军. 用于轨道交通超级电容储能的双向DC-DC变换器拓扑分析与比较[J]. 电工技术学报, 2013, 28(1): 109-116. Wu Wei, Xie Shaojun.Analyzing and comparing bi-direction DC-DC converters for ultra-capacitor based energy storage system in urban rail transit[J]. Transactions of China Electrotechnical Society, 2013, 28(1): 109-116. [16] 武伟, 谢少军, 张曌, 等. 基于MMC双向DC-DC变换器的超级电容储能系统控制策略分析与设计[J]. 中国电机工程学报, 2014, 34(27): 4568-4575. Wu Wei, Xie Shaojun, Zhang Zhao, et al.Analysis and design of control strategy for MMC-BDC based ultra-capacitors energy storage systems[J]. Pro- ceedings of the CSEE, 2014, 34(27): 4568-4575. [17] Giri R, Ayyanar R, Ledezma E, Input-series and output-series connected modular DC-DC converters with active input voltage and output voltage sharing[C]//Nineteenth Annual IEEE, North Carolina, 2004: 1751-1754. [18] 毕恺韬, 安群涛, 孙东阳, 等. 基于子模组工况分析的模块化多电平储能系统开路故障诊断方[J/OL]. 电工技术学报. [2017-12-24]. https://doi.org/10. 19595/j. cnki.1000-6753.tces.161255. Bi Kaitao, An Quntao, Sun Dongyang, et al, Modular multilevel energy storage system open circuit diagnostic method based on sub-module operation analysis[J/OL]. Transactions of China Electro- technical Society. [2017-12-24]. https://doi.org/10. 19595/j. cnki.1000-6753.tces.161255. [19] Sha D, Deng K, Liao X, Duty cycle exchanging control for input-series-output-series connected two PS-FB DC-DC converters[J]. IEEE Transactions on Power Electronic, 2012, 27(3): 1490-1501. [20] 陈武, 曹远志, 崔红芬, 等. 模块化输入串联输出串联高压直流组合系统分布式均压控制策略[J]. 电工技术学报, 2015, 30(3): 187-195. Chen Wu, Cao Zhiyuan, Cui Hongfen, et al.Modular input-series output-series DC high voltage system with distributed voltage sharing control strategy control strategy of input-series output-series inverters system[J]. Transactions of China Electrotechnical Society, 2015, 30(3): 187-195. [21] Chen W, Wang G.Decentralized voltage-sharing control strategy for fully modular input-series- output-series system with improved voltage regula- tion[J]. IEEE Transactions on Industrial Electronics, 2015, 62(5): 2777-2787. [22] Xu Q W, Xiao J F, Hu X L, et al.A decentralized power management strategy for hybrid energy storage system with autonomous bus voltage restoration and state of charge recovery[J]. IEEE Transactions on Industrial Electronics, 2017, 64(7): 2764-2776. [23] 支娜, 张辉, 肖曦. 提高直流微电网动态特性的改进下垂控制策略研究[J]. 电工技术学报, 2016, 31(3): 31-39. Zhi Na, Zhang Hui, Xiao Xi.Research on the improved droop control strategy for improving the dynamic characteristics of DC microgrid[J]. Transa- ctions of China Electrotechnical Society, 2016, 31(3): 31-39.
2018, Vol. 33 
