Abstract:Energy-balancing control is one of the key problems to be solved urgently in energy storage system. This paper proposes an energy self-balancing control strategy based on cascaded multilevel super capacitor energy storage system. This strategy adopts super capacitor state-of-charge (SOC) to build separated half bridge sub-module current loops. Accordingly, the average operating current of each module can be independently controlled according to super capacitor SOC. Therefore, the proposed strategy can directly use system current to achieve energy balance between sub-modules without affecting the current response of system. Meanwhile, to solve the issue of the balancing speed reduction in the process of energy balance, a weight coefficient based on SOC is designed to promote the balancing speed. The proposed strategy does not affect the ability of energy storage system to stabilize DC bus voltage, avoids the external balancing circuit, and simplifies the entire control of energy storage system. At last, the proposed strategy is verified by the experimental results.
毕恺韬, 安群涛, 段建东, 凡绍桂, 孙力. 基于级联多电平直流变换器的超级电容储能系统能量自均衡控制策略[J]. 电工技术学报, 2018, 33(8): 1919-1928.
Bi Kaitao, An Quntao, Duan Jiandong, Fan Shaogui, Sun Li. Self-Balancing Control Strategy for Super Capacitor Energy Storage System Based on Cascaded Multilevel DC-DC Converter. Transactions of China Electrotechnical Society, 2018, 33(8): 1919-1928.
[1] Nehrir M H, Wang C, Strunz K, et al, A review of hybrid renewable/alternative energy systems for electric power generation: configurations, control, and applications[C]//Power and Energy Society General Meeting, San Diego, CA, 2011: 392-403. [2] Li S, Mi C C, Zhang M.A high-efficiency active battery balancing circuit using multiwinding trans- former[J]. IEEE Transactions on Industry Application, 2013, 49(1): 198-207. [3] 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]. Transa- ctions of China Electrotechnical Society, 2016, 31(14): 84-92. [4] 倪双舞, 苏建徽. 以电容储能作为外环反馈变量的双闭环多电平整流器控制策略[J]. 电工技术学报, 2016, 31(9): 92-100. Ni Shuangwu, Su Jianhui.A dual closed loop control strategy of the multi-level rectifier using capacitor energy as the outer loop variable[J]. Transactions of China Electrotechnical Society, 2016, 31(9): 92-100. [5] 赵坤, 王椹榕, 王德伟, 等. 车载超级电容储能系统间接电流控制策略[J]. 电工技术学报, 2011, 26(9): 124-129. Zhao Kun, Wang Shenrong, Wang Dewei, et al.Indirect current control strategy of on-board supercapacitor energy storage system of railway vehicle[J]. Transactions of China Electrotechnical Society, 2011, 26(9): 124-129. [6] Gholizadeh M, Salmasi F R.Estimation of state of charge unknown nonlinearities state of health of a lithium-ion battery based on a comprehensive unobservable model[J]. IEEE Transactions on Industrial Electronics, 2014, 61(3): 1335-1344. [7] 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]. Proceedings of the CSEE, 2014, 34(27): 4568-4575. [8] 赵坤. 城轨交通车载超级电容储能系统能量管理及容量配置研究[D]. 北京: 北京交通大学, 2013. [9] 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. [10] Pascual C, Krein P T.Switched capacitor system for automatic series battery equalization[C]//12th IEEE Applied Power Electronics Conference, Charlotte, North Carolina, 1997: 439-446. [11] 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 Electronics, 2012, 27(7): 3234-3242. [12] 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 Electronics, 2016, 31(7): 4916-4929. [13] 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): 109-416. 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): 109-416. [14] Huang W, Abu Qahouq J.Energy sharing control scheme for state-of-charge balancing of distributed battery energy storage system[J]. IEEE Transactions on Power Electronics, 2015, 62(5): 2764-2776. [15] 艾洪克, 吴俊勇, 郝亮亮, 等. 级联式储能系统中电池自均衡控制策略研究[J]. 电工技术学报, 2015, 30(14): 442-449. Ai Hongke, Wu Junyong, Hao Liangliang, et al.Research on battery self-balancing control strategy in cascade energy storage system[J]. Transactions of China Electrotechnical Society, 2015, 30(14): 442-449. [16] 金一丁, 宋强, 刘文华. 大容量链式电池储能系统及其充放电均衡控制[J]. 电力自动化设备, 2011, 31(3): 6-11. Jin Yiding, Song Qiang, Liu Wenhua.Large scaled cascaded battery energy storage system with charge/ discharge balancing[J]. Electric Power Automation Equipment, 2011, 31(3): 6-11. [17] 喻锋, 王西田, 林卫星, 等. 一种快速的模块化多电平换流器电压均衡控制策略[J]. 中国电机工程学报, 2015, 35(4): 929-934. Yu Feng, Wang Xitian, Lin Weixing, et al.A fast voltage balancing control method for modular multilevel converter[J]. Proceedings of the CSEE, 2015, 35(4): 929-934. [18] 杨晓峰, 林智钦, 郑琼林. 模块组合多电平变换器的研究综述[J]. 中国电机工程学报, 2013, 33(6): 1-15. Yang Xiaofeng, Lin Zhiqin, Zheng Trillion Q.A review of modular multilevel converters[J]. Pro- ceedings of the CSEE, 2013, 33(6): 1-15. [19] Wang K, Li Y, Zheng Z, et al.Voltage balancing and fluctuation suppression methods of floating capacitors in a new modular multilevel converter[J]. IEEE Transactions on Industrial Electronics, 2013, 60(5): 1943-1954. [20] Li Z, Wang P, Zhu H, et al.An improved pulse width modulation method for chopper-cell-based modular multilevel converters[J]. IEEE Transactions on Power Electronics, 2012, 27(8): 3472-3481.