Electric quantity balance control method for tandem power battery pack

Abstract

The invention relates to an electric quantity balance control method for a tandem power battery pack. The method comprises the following steps: (S1) calculating each monomer remaining capacity according to monomer volume and monomer battery charging state SOC in the tandem power battery pack, and sorting the monomer remaining capacities from small to large; (S2) calculating monomer remaining capacity standard difference a in the tandem power battery pack; (S3) if the monomer remaining capacity standard difference a is larger than a dispersion set value b, entering a step (S4), and otherwise, carrying out electric quantity balance operation; and (S4) balancing each monomer remaining capacity according to a maximum value-minimum value pairing balance rule and a secondary maximum value-secondary minimum value pairing balance rule of the remaining capacity. Compared with an existing electric quantity balance control method for the tandem power battery pack, the method disclosed by the invention has the advantages that the complete charging and discharging of the tandem power battery pack can be realized, the utilization efficiency of the energy of the tandem power battery pack is improved, and the service life of the tandem power battery pack is prolonged.

Description

technical field [0001] The invention belongs to the field of battery research, and in particular relates to a power balance control method for series-connected power battery packs. Background technique [0002] The power battery pack is the energy source of electric vehicles. In order to meet the performance requirements of electric vehicles, it is necessary to form a power battery pack by connecting thousands of single cells in series and in parallel. Due to different manufacturing processes, grouping methods and operating conditions The inconsistencies in parameters such as capacity, internal resistance, and self-discharge rate among the cells will reduce the energy utilization efficiency of the power battery pack, accelerate battery aging, and limit the power of the power battery pack. The balance control of each monomer is carried out. [0003] At present, the equalization algorithm is mainly divided into the equalization control based on the voltage and the equalizatio...

AI Technical Summary

Problems solved by technology

Based on the voltage scheme, the equalization algorithm aims at the real-time cell voltage consistency, but when the cell capacity is inconsistent, there may be a wrong balance problem that some cells need to be charged and balanced at a certain moment, but need to be discharged at another moment.

However, the SOC-based equalization algorithm aims at the real-time SOC consistency. When the cell capacity is inconsistent, some cells may also need to be charged and balanced at a certain moment, but they need to be discharged at another moment. Misbalanced problem

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