A battery balancing topology and balancing control method based on a full-bridge cascaded battery

Abstract

The invention relates to a full-bridge cascaded battery balancing topology and balancing control method, belonging to the technical field of battery management. The battery and the full-bridge module are connected in parallel to form a battery module, and multiple battery modules are cascaded to form a battery pack; during the charging and discharging process, the full-bridge module in the battery pack is controlled to work in different states according to the SOC of the single battery, so that the single The battery is connected to the battery pack in the forward or reverse direction, and the single battery is charged while the whole battery is discharged; the single battery is discharged while the whole battery is charged; the SOC of the single battery in the battery pack tends to be the same. Ensures that the output voltage of the entire battery pack remains constant during equalization. The post-stage DC-DC circuit ensures that the voltage mutation after equalization will not affect the output of the entire battery pack. Advantages: The reverse connection of the single battery to the battery pack can complete the equalization work well, alleviate the battery polarization effect caused by the traditional constant current charging, and realize the removal of the faulty battery. The set switching threshold reduces the number of SOC sorting and improves the running speed of the algorithm.

Description

technical field [0001] The invention relates to the technical field of battery management, in particular to a full-bridge cascaded battery equalization topology and an equalization control method. Background technique [0002] With the rapid development of electric vehicles, batteries have been widely used as the power source of electric vehicles. However, due to the low voltage of battery cells, it is necessary to connect multiple batteries in series and parallel to increase the voltage and capacity of the battery pack. However, due to the influence of the battery manufacturing process, the use environment and other factors, the parameters of the single battery cannot be completely consistent, and the battery pack cannot fully function due to the short board effect, and the efficiency is reduced. And in the process of charging and discharging, it is easy to cause the problem of overcharging and overdischarging, which reduces the service life of the battery and increases po...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a battery equalization topology and equalization control method based on a full-bridge cascaded battery, which solves the problem of performance degradation of the battery pack caused by the inconsistency of the single battery, improves the safety and service life of the battery, improves the equalization speed, and Reduce battery polarization during charging and discharging

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