Energy Storage Science and Technology ›› 2023, Vol. 12 ›› Issue (5): 1655-1663.doi: 10.19799/j.cnki.2095-4239.2022.0759

• Energy Storage System and Engineering • Previous Articles     Next Articles

Optimal equalization control of battery energy storage systems in power distribution station area

Yi WU1(), Yahong MENG1, Yi ZHANG1, Tie ZHOU1, Ji LIU1, Yewen WEI2()   

  1. 1.Binhai Power Supply Branch of State Grid Jiangsu Electric Power Co. , LTD. , Yancheng 224500, Jiangsu, China
    2.College of Electrical Engineering & New Energy in CTGU, Yichang 443000, Hubei, China
  • Received:2022-12-20 Revised:2023-01-12 Online:2023-05-05 Published:2023-05-29
  • Contact: Yewen WEI E-mail:weiyewen8@126.com;weiyewen@ctgu.edu.cn

Abstract:

The power system distribution station area is the critical unit of electric energy distribution. Its core component, the energy storage battery pack, comprises many cells. Given the inevitable consistency difference of each cell in the energy storage battery pack, an adaptive group equalization control method for an energy storage battery pack is proposed based on K-means clustering. First, an equalization topology is introduced to transfer equalization energy between cells or battery modules containing any number of cells. Second, the idea of group equalization is introduced, and the adjacent cells that need to be charged and discharged are clustered into groups using the K-means clustering algorithm to realize a balanced energy transfer between battery groups containing a different number of adjacent cells. Finally, simulation experiments verify the proposed cluster group equalization control. Compared with the range-based cell-to-cell equalization control, cluster group equalization control improves the equalization speed by 34.8%, 19.8%, and 17.6%, respectively, under the initial SOC distribution conditions: high in the middle, low on both sides; high on both sides, low in the middle; and balanced distribution. Herein, the idea of cluster equalization for an energy storage battery pack composed of a large number of cells is proposed, which is conducive to the equalization speed of the energy storage battery pack, thereby improving its energy utilization rate and cycle life and promoting the application of the energy storage battery pack.

Key words: K-means, consistency differences, energy storage battery pack, group equalization, equalization speed

CLC Number: