Open Access

ARTICLE

A New Equalization Method for Lithium-Ion Battery Packs Based on CUK Converter

Yu Zhang, Sheng Tian^*, Yongkang Zhang
School of Electrical and Electronic Engineering, Hubei University of Technology, Wuhan, 430000, China
* Corresponding Author: Sheng Tian. Email:

Energy Engineering https://doi.org/10.32604/ee.2024.047247

Received 31 October 2023; Accepted 29 December 2023; Published online 22 February 2024

Abstract

Aiming at the traditional CUK equalizer can only perform energy equalization between adjacent batteries, if the two single batteries that need to be equalized are far away from each other, there will be the problem of longer energy transmission path and lower equalization efficiency, this paper optimizes the CUK equalizer and optimizes its peripheral selection circuit, which can support the equalization of single batteries at any two positions. The control strategy adopts the open-circuit voltage (OVC) of the battery and the state of charge (SOC) of the battery as the equalization variables, and selects the corresponding equalization variables according to the energy conditions of the two batteries that need to be equalized, and generates the adaptive equalization current with an adaptive PID controller in order to improve the equalization efficiency. Simulation modeling is performed in Matlab/Simulink 2021b, and the experimental results show that the optimized CUK equalizer in this paper improves the equalization time by 25.58% compared with the traditional CUK equalizer. In addition, compared with the mean value difference (MVD) method, the adaptive PID method reduces the equalization time by about 30% in the static and charging and discharging experimental environments, which verifies the superiority of this equalization scheme.

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Keywords

battery balancing; CUK equalizer; adaptive PID; SOC

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