Lithium battery balancing control - including matlab simulation model + paper

Abstract
Research on the design and control strategy of electric vehicle battery pack balancing system.
When lithium power battery cells are connected in series and used in pure electric vehicles, due to
the inconsistency , the performance of the battery pack will be degraded. The available capacity and lifespan are much lower than that of a single battery, and the battery performance cannot be
fully utilized, which reduces the driving range of electric vehicles and also increases the cost of use. As
an important functional module of the battery management system, the balancing management module can monitor the battery pack status information in real time and balance the battery pack according to the corresponding control strategy
, thereby improving the impact of battery pack inconsistency during use and improving the battery life.
Improve group capacity utilization and increase driving range.
This article relies on the "Power Battery Management System Development and Balancing Technology Research" jointly developed by a company and Jilin University
to conduct research on the balancing technology-related contents of the project.
Based on a full understanding of battery pack balancing technology research at home and abroad, this paper takes the series lithium power battery pack as the research object, focusing
on the balancing topology with relatively simple balancing control and high balancing efficiency, and its corresponding control strategy.
1. The reasons for the inconsistency of the battery pack are analyzed from the mechanism, and the manifestations of the inconsistency of the battery pack
in different characteristic parameters (voltage, internal resistance, SOC) are explained. The comparative analysis is based on voltage and state of charge (SOC). )
as a balancing variable, and finally decided to use voltage as the balancing variable of the battery pack in different states.
2. Comparatively analyze common balancing topologies,
evaluate them from the aspects of balancing speed, balancing efficiency, and ease of circuit control, and select an energy non-dissipative balancing topology based on a flyback transformer.
The parameters of the flutter structure were designed, a balanced circuit simulation model was built, simulation debugging and structural improvement were carried out, and it was determined that the "cutting"
Circuit control parameters in two modes: "peak" and "valley filling". 3. In order to avoid excessive charging time and misjudgment of the system's balance due to irregular discharge current of the battery pack, two equalization modes for charging and parking
are proposed.