Journal of Northeastern University Natural Science ›› 2020, Vol. 41 ›› Issue (4): 492-498.DOI: 10.12068/j.issn.1005-3026.2020.04.007

• Information & Control • Previous Articles     Next Articles

Online Estimation Method for State of Health of Electric Vehicle Power Battery

LIU Fang1,2,3, LIU Xin-yi1, SU Wei-xing1,2, LIN Hui4   

  1. 1. School of Computer Science and Technology, Tiangong University, Tianjin 300387, China; 2. State Key Laboratory of Process Automation in Mining & Meallurgy/Beijing Key Laboratory of Process Automation in Mining & Metallurgy, BGRIMM Technology Group,Beijing 100160, China; 3. Tianjin Qingyuan Electric Vehicle Limited Liability Company, Tianjin 300462, China; 4. Neusoft Reach Automative Technology Co. Ltd., Shenyang 110179, China.
  • Received:2019-08-21 Revised:2019-08-21 Online:2020-04-15 Published:2020-04-17
  • Contact: SU Wei-xing
  • About author:-
  • Supported by:
    -

Abstract: An effective estimation method for online operation of electric vehicle power battery SOH was proposed. The advantage is that it only relies on the voltage and current data measured by the battery management system in real time, without the need of offline battery life decay curve and the initial state of the battery. Therefore, it is more in line with the actual needs of electric vehicles for SOH estimation. Based on the Thevenin and OCV-SOC models, a battery model with time and SOH as hidden variables was constructed in the battery constant-current charging mode. Based on this battery model, a fast solving algorithm based on NLS(nonlinear least square) initialization GA search range was proposed for online parameter identification, and the real-time SOH estimation value of electric vehicle was obtained. The verification results showed that the SOH estimation algorithm has good practicability and high estimation accuracy.

Key words: electric vehicle, SOH online estimation, battery model, genetic algorithm, nonlinear least squares

CLC Number: