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摘要: 荷電狀態(State of charge, SOC)估計是電池管理系統的核心功能之一,它在電動汽車的生命周期中起著重要作用。針對鋰離子電池溫度影響模型參數,進而導致SOC估計不準確的問題,本文提出了基于魯棒H∞濾波的SOC估計方法。首先,以二階Thevenin等效電路模型做為鋰離子電池基礎模型,并將溫度對電池模型參數的影響建模為標稱電阻值和電池總容量的加性變量,視溫度變化為系統的外部擾動。其次,采用滑動線性法對電池模型進行線性化,并在此基礎上運用線性矩陣不等式技術設計了對SOC進行估計的魯棒H∞濾波器。最后,分別采用四種不同類型的動態電流激勵進行仿真實驗驗證,并將SOC的估計結果與kalman濾波對SOC的估計結果進行對比。結果表明所設計的魯棒H∞濾波器能夠實現對SOC更為準確的跟蹤,同時對外部擾動具有較好的魯棒性。Abstract: The state of charge (SOC) estimation is one of the core functions of the battery management system; it can play a significant role in the life cycle of electric vehicles. The SOC estimation method has attracted considerable research attention in recent years, particularly about improving estimation accuracy. However, most studies are limited by only focusing on known or fixed battery model parameters and not considering their temperature dependence. This indicates a need to explore how the lithium-ion battery temperature affects the model parameters, which leads to inaccurate SOC estimation. The principal objective of this study is to investigate the robust H∞ filter-based method for the problem that temperature affects battery model parameters and thus leads to inaccurate SOC estimation. First, the second-order Thevenin equivalent circuit model with two parallel resistor–capacitor pairs is taken as the basic model of the lithium-ion battery. The influence of temperature on battery model parameters is modeled as an additive variable of the nominal resistance value and the total battery capacity, and the temperature change is considered an external disturbance of the system. Afterward, the sliding linear method is used to linearize this battery model; on this basis, a robust H∞ filter for SOC estimation is designed using linear matrix inequality technology. Finally, the effectiveness of the proposed approach is verified using four different types of dynamic current load profiles (the BJDST-Beijing Dynamic Stress Test, FUDS-Federal Urban Driving Schedule, US06-US06 Highway Driving Schedule and BJDST-FUDS-US06 joint dynamic test) compared with the Kalman filter-based SOC estimation method. The simulation analysis results indicate that the proposed SOC estimation approach can realize a higher SOC estimation accuracy even if the model parameters vary with temperature, and it has good robustness to external disturbances.
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Key words:
- lithium-ion battery /
- SOC estimation /
- model parameter perturbation /
- model linearization /
- H∞ filter
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表 1 電池模型參數
Table 1. Battery model parameters
R0 / Ω R1 / Ω R2 / Ω C1 / F C2 / F Q /(A·h) a b 0.00867 0.0124 0.0123 2239 41831 2.3 1/3 3.05 表 2 SOC估計及其估計誤差的均方根值
Table 2. RMS value of SOC estimation and estimation error
Dynamic test Model output
(RMS)H∞ filter
(RMS)Kalman filter
(RMS)BJDST 0.4874 0.4879 0.4861 BJDST estimation error 0.0019 0.0041 FUDS 0.4703 0.4704 0.4694 FUDS estimation error 0.0018 0.0036 US06 0.4991 0.4992 0.4986 US06 estimation error 0.0019 0.0043 BJDST?FUDS?US06 0.3186 0.3186 0.3175 BJDST?FUDS?US06 estimation error 0.0022 0.0033 259luxu-164 -
參考文獻
[1] Wang X L, Jin H Q, Liu X Y. Online estimation of the state of charge of a lithium-ion battery based on the fusion model. Chin J Eng, 2020, 42(9): 1200王曉蘭, 靳皓晴, 劉祥遠. 基于融合模型的鋰離子電池荷電狀態在線估計. 工程科學學報, 2020, 42(9):1200 [2] Su W, Zhong G B, Shen J N, et al. The progress in fault diagnosis techniques for lithium-ion batteries. Energy Storage Sci Technol, 2019, 8(2): 225 doi: 10.12028/j.issn.2095-4239.2018.0195蘇偉, 鐘國彬, 沈佳妮, 等. 鋰離子電池故障診斷技術進展. 儲能科學與技術, 2019, 8(2):225 doi: 10.12028/j.issn.2095-4239.2018.0195 [3] Liu X T, Sun Z C, He Y, et al. SOC estimation method based on lithium-ion cell model considering environmental factors. J Southeast Univ Nat Sci Ed, 2017, 47(2): 306 doi: 10.3969/j.issn.1001-0505.2017.02.018劉新天, 孫張馳, 何耀, 等. 基于環境變量建模的鋰電池SOC估計方法. 東南大學學報(自然科學版), 2017, 47(2):306 doi: 10.3969/j.issn.1001-0505.2017.02.018 [4] Feng D W, Lu C, Chen Y, et. al. Battery state-of-charge online estimation based on H∞ observer with current debasing and noise distributions. J Univ Electron Sci Technol China, 2017, 46(4): 547 doi: 10.3969/j.issn.1001-0548.2017.04.012馮代偉, 陸超, 陳勇, 等. 具有電流偏差和噪聲擾動的H∞觀測器在線估計電池SoC狀態. 電子科技大學學報, 2017, 46(4):547 doi: 10.3969/j.issn.1001-0548.2017.04.012 [5] Lin X F, Kim Y, Mohan S, et al. Modeling and estimation for advanced battery management. Ann Rev Control Rob Autonom Syst, 2019, 2: 393 doi: 10.1146/annurev-control-053018-023643 [6] Miao Z X, Xu L, Disfani V R, et al. An SOC-based battery management system for microgrids. IEEE Trans Smart Grid, 2014, 5(2): 966 doi: 10.1109/TSG.2013.2279638 [7] Tan F M, Zhao J J, Wang Q. A novel robust UKF algorithm for SOC estimation of traction battery. Autom Eng, 2019, 41(8): 944談發明, 趙俊杰, 王琪. 動力電池SOC估計的一種新型魯棒UKF算法. 汽車工程, 2019, 41(8):944 [8] Cheng K W E, Divakar B P, Wu H J, et al. Battery-management system (BMS) and SOC development for electrical vehicles. IEEE Trans Veh Technol, 2011, 60(1): 76 doi: 10.1109/TVT.2010.2089647 [9] Dey S, Ayalew B. Nonlinear observer designs for state-of-charge estimation of lithium-ion batteries // 2014 American Control Conference. Portland, 2014: 248 [10] Bhangu B S, Bentley P, Stone D A, et al. Nonlinear observers for predicting state-of-charge and state-of-health of lead-acid batteries for hybrid-electric vehicles. IEEE Trans Veh Technol, 2005, 54(3): 783 doi: 10.1109/TVT.2004.842461 [11] He H W, Xiong R, Fan J X. Evaluation of lithium-ion battery equivalent circuit models for state of charge estimation by an experimental approach. Energies, 2011, 4(4): 582 doi: 10.3390/en4040582 [12] Ding Z T, Deng T, Li Z F, et al. SOC estimation of lithium-ion battery based on ampere hour integral and unscented Kalman filter. China Mech Eng, 2020, 31(15): 1823 doi: 10.3969/j.issn.1004-132X.2020.15.009丁鎮濤, 鄧濤, 李志飛, 等. 基于安時積分和無跡卡爾曼濾波的鋰離子電池SOC估算方法研究. 中國機械工程, 2020, 31(15):1823 doi: 10.3969/j.issn.1004-132X.2020.15.009 [13] Jin B W, Qiao H M, Pan T H, et al. Lithium battery SOC estimation based on internal resistance power consumption. Autom Eng, 2020, 42(8): 1008靳博文, 喬慧敏, 潘天紅, 等. 基于內阻功率消耗的鋰電池SOC估計. 汽車工程, 2020, 42(8):1008 [14] Codeca F, Savaresi S M, Rizzoni G. On battery state of charge estimation: A new mixed algorithm // 2008 IEEE International Conference on Control Applications. San Antonio, 2008: 102 [15] Hu Y R, Yurkovich S. Battery state of charge estimation in automotive applications using LPV techniques // Proceedings of the 2010 American Control Conference. Baltimore, 2010: 5043 [16] Hu Y, Yurkovich S. Battery cell state-of-charge estimation using linear parameter varying system techniques. J Power Sources, 2012, 198: 338 doi: 10.1016/j.jpowsour.2011.09.058 [17] Zhang Y, Zhang C H, Zhang X F. State-of-charge estimation of the lithium-ion battery system with time-varying parameter for hybrid electric vehicles. IET Control Theory Appl, 2013, 8(3): 160 [18] Liu C Z, Zhu Q, Li L, et al. A state of charge estimation method based on H∞ observer for switched systems of lithium-ion nickel-manganese-cobalt batteries. IEEE Trans Ind Electron, 2017, 64(10): 8128 doi: 10.1109/TIE.2017.2701766 [19] Dey S, Ayalew B, Pisu P. Nonlinear robust observers for state-of-charge estimation of lithium-ion cells based on a reduced electrochemical model. IEEE Trans Control Syst Technol, 2015, 23(5): 1935 doi: 10.1109/TCST.2014.2382635 [20] Wang T H, Martinez-Molina J J, Sename O. H∞ observer-based battery fault estimation for HEV application. IFAC Proc Vol, 2012, 45(30): 206 doi: 10.3182/20121023-3-FR-4025.00021 [21] Zhu Q, Li L, Hu X S, et al. H∞-based nonlinear observer design for state of charge estimation of lithium-ion battery with polynomial parameters. IEEE Trans Veh Technol, 2017, 66(12): 10853 doi: 10.1109/TVT.2017.2723522 [22] Dreef H J, Beelen H P G J, Donkers M C F. LMI-based robust observer design for battery state-of-charge estimation // 2018 IEEE Conference on Decision and Control (CDC). Miami Beach, 2018: 5716 [23] Wang B J, Liu Z Y, Li S E, et al. State-of-charge estimation for lithium-ion batteries based on a nonlinear fractional model. IEEE Trans Control Syst Technol, 2017, 25(1): 3 doi: 10.1109/TCST.2016.2557221 [24] Lu W, Xu D, Yang Q X, et al. Fractional model and state-of-charge of lithium battery. J Xi'an Jiaotong Univ, 2017, 51(7): 124魯偉, 續丹, 楊晴霞, 等. 鋰電池分數階建模與荷電狀態研究. 西安交通大學學報, 2017, 51(7):124 [25] Lofberg J. YALMIP: A toolbox for modeling and optimization in MATLAB // 2004 IEEE International Conference on Robotics and Automation. New Orleans, 2004: 284 [26] L?fberg J. Modeling and solving uncertain optimization problems in YALMIP // Proceedings of the 17th IFAC World Congress. Seoul, 2008: 1337 -