Energy Storage Science and Technology ›› 2022, Vol. 11 ›› Issue (2): 660-666.doi: 10.19799/j.cnki.2095-4239.2021.0411

• Energy Storage Test: Methods and Evaluation • Previous Articles     Next Articles

State estimation of lithium-ion battery based on dual adaptive Kalman filter

Pengchao HUANG1(), Jiaqiang E2   

  1. 1.Liuzhou Vocational Technical College School of Automotive Engineering, Liuzhou 545616, Guangxi, China
    2.College of Mechanical and Vehicle Engineering, Hunan University, Changsha 410082, Hunan, China
  • Received:2021-08-09 Revised:2021-08-27 Online:2022-02-05 Published:2022-02-08
  • Contact: Pengchao HUANG E-mail:hpch_edu@163.com

Abstract:

An accurate lithium-ion battery model is very important to ensure the reliability of the battery. Accurate estimation of state of charge (SOC) ensures the safety and efficient operation of specific applications. To improve the estimation accuracy of SOC, an equivalent circuit model is established and the parameters are identified using bias compensation recursive least squares (BCRLS) of the forgetting factor. The SOC is then estimated using the adaptive unscented Kalman filter (AUKF) algorithm. The AUKF algorithm defined by weight vectors was proposed to improve the estimation accuracy of SOC because of the vulnerability of the unscented Kalman filter technique to nonlinear variables. However, the internal characteristics of the battery will change during the discharge process, and the ohmic internal resistance of the battery will have a direct effect on the SOC estimations. Based on this, we propose a dual AUKF to further improve the estimation accuracy of SOC. Compared with other algorithms, the experimental results show that the proposed algorithm's error in estimating SOC is less than 2%, demonstrating the effectiveness of the algorithm.

Key words: lithium ion battery, state of charge (SOC), bias compensation recursive least squares, weight vectors, dual adaptive unscented Kalman filter

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