A Monte Carlo simulator to investigate cell‐to‐cell deviation in a grid‐tied battery pack. Issue 13 (9th April 2022)

• Record Type: Journal Article
• Authors: Wang, Zeyuan; Wang, Zhuo; Davidson, Jonathan; Foster, Martin; Gladwin, Daniel
• Is Part Of: IET power electronics. Volume 15:Issue 13(2022)
• Page Start: 1264
• Page End: 1278
• Publication Date: 2022-04-09
• Subjects: Power electronics -- Periodicals; 621.31705
• DOI: 10.1049/pel2.12289
• Languages: English
• ISSNs: 1755-4535

Abstract

Abstract: Battery energy storage systems (BESSs) are commonly used in smart grids. Voltage deviation or imbalance among cells generally exists in multi‐cell battery packs. This work presents a study of the voltage deviation‐related phenomena observed during the operation of a grid‐tied BESS, Willenhall Energy Storage System (WESS), including the voltage deviation changes during full range cycle and the cut‐off mechanism activated by it. Electroimpedance spectroscopy measurements and equivalent circuit modelling were conducted on the same type of cell as that used in WESS to obtain cell‐equivalent circuit parameter distributions (the standard deviation and mean). Cell voltage deviation in a WESS‐sized battery pack (> 21k cells) was studied using Monte Carlo simulation through a proposed cell level battery simulator. Both experiments and simulations reveal that high cell voltage deviation emerges at the low and high state‐of‐charge zones where the cell internal resistance has a large value and large extent of deviation.