An SOC estimation approach based on adaptive sliding mode observer and fractional order equivalent circuit model for lithium-ion batteries

• Published in: Communications in nonlinear science & numerical simulation Vol. 24; no. 1-3; pp. 127 - 144
• Main Authors: Zhong, Fuli, Li, Hui, Zhong, Shouming, Zhong, Qishui, Yin, Chun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-07-2015
• Subjects: Adaptive sliding mode observer; Computer simulation; Electric charge; Equivalent circuits; Fractional order equivalent circuit model; Lithium-ion batteries; Lithium-ion battery; Mathematical analysis; Mathematical models; Sliding mode; SOC estimation; Vibration; Lithium-ion battery; SOC estimation; Adaptive sliding mode observer; Fractional order equivalent circuit model
• ISSN: 1007-5704; 1878-7274
• DOI: 10.1016/j.cnsns.2014.12.015

•This paper proposes an SOC estimation method for lithium-ion battery.•A FO equivalent circuit model is employed to model the dynamics of a battery.•A novel adaptive sliding mode design method is proposed.•More accurate estimation is obtained with designed adaptive SMOs.•Multiple simulation experiments show the effectiveness of the proposed method.
A state of charge (SOC) estimation approach based on an adaptive sliding mode observer (SMO) and a fractional order equivalent circuit model (FOECM) for lithium-ion batteries is proposed in this paper. In order to design the adaptive sliding mode observer (SMO) for the SOC estimation, the state equations based on a FOECM of battery are derived. A new self-adjusting strategy for the observer gains is presented to adjust the observer in the estimating process, which helps to reduce chattering and convergence time. Furthermore, a continuous and smooth function called hyperbolic tangent function is applied to balance the chattering affection and the disturbance. At last, a battery simulation model is established to test the SOC estimation performance of the designed SMOs, and the results show the proposed approach is feasible and effective.