Title: New approach of SOC estimation method for lithium-ion battery/ultra-capacity hybrid system based on multi-model strategy

Authors: Qiuting Wang; Wei Qi

Addresses: Department of Electrical and Information Engineering, Zhejiang University City College, 51 Huzhou Road, Hangzhou, 310015, China ' Department of Electrical and Information Engineering, Zhejiang University City College, 51 Huzhou Road, Hangzhou, 310015, China

Abstract: A new state of charge (SOC) estimation method based on multi-model strategy (MMS) is proposed. For lithium-ion battery/ultra-capacity hybrid system, the model precision and the real-time performance will be satisfied at the same time. New modelling method for the battery energy storage system is presented. The main efforts of our works are, firstly, the hybrid system model is established based on multi-model strategy. Secondly, the model parameters are updated using extended Kalman filter (EKF) algorithm and the electric quantity of lithium-ion battery is estimated using unscented Kalman filter (UKF) algorithm. Lastly, the experiments were conducted under the dynamic working condition and the NEDC working condition. The results indicate that the SOC estimation accuracy based on MMS is better than that without the strategy.

Keywords: lithium-ion battery; SOC estimation; multi-model strategy; joint Kalman filtering algorithm; New European Driving Cycle; NEDC.

DOI: 10.1504/IJPELEC.2022.126613

International Journal of Power Electronics, 2022 Vol.16 No.4, pp.470 - 482

Received: 21 Jul 2020
Accepted: 27 Mar 2021

Published online: 31 Oct 2022 *

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