Electric Power ›› 2024, Vol. 57 ›› Issue (6): 18-26.DOI: 10.11930/j.issn.1004-9649.202401003

• Key Safety Technology of Lithium-Ion Battery Body for Energy Storage • Previous Articles     Next Articles

State of Charge Estimation of Energy Storage Battery Pack under Typical Peak/Frequency Modulation Conditions

Muyu ZHU1(), Hongzhong MA1(), Pengyu GUO2(), Wenjing XUAN1   

  1. 1. College of Electrical and Power Engineering, Hohai University, Nanjing 211100, China
    2. State Grid Jiangsu Electric Power Co., Ltd., Nanjing 210024, China
  • Received:2024-01-02 Accepted:2024-04-01 Online:2024-06-23 Published:2024-06-28
  • Supported by:
    This work is supported by National Natural Science Foundation of China (Vibration (Acoustic) Mechanism Analysis and Electromechanical (Acoustic) Fusion Diagnosis of Internal Faults in Doubly-Fed Induction Generator, No.51577050) and Science & Technology Project of State Grid Jiangsu Electric Power Co., Ltd. (Research on Safety Performance of Energy Storage Battery Under Different Network Storage Interaction Modes, No.J2022158).

Abstract:

To address the issue of low estimation accuracy of the state of charge (SOC) for an energy storage battery pack under typical energy storage conditions of a power grid, this paper proposes a new SOC estimation model based on kernel principal component analysis (KPCA), pelican optimization algorithm (POA), and bidirectional gated recurrent unit (BiGRU). By designing the charge and discharge experiment of a battery pack under the condition of peak/frequency modulation, the paper extracts the fusion features of SOC change from the data as the model input. BiGRU networks are constructed under different working conditions, and POA is utilized to optimize its hyperparameters to improve the model's performance. The effectiveness of the model is further verified under mixed conditions. The results show that the proposed model has better SOC estimation performance and stronger robustness, which can improve the SOC estimation accuracy of energy storage battery packs under complex energy storage conditions.

Key words: energy storage battery pack, state of charge estimation, peak and frequency modulation, pelican optimization, bidirectional gated recurrent unit