Design and Modeling of Battery Management System for Electric Vehicle Applications

Abstract

The Battery Management System Plays A Crucial Role In Ensuring The Safe And Efficient Operation Of Electric Vehicle Batteries. However, Accurately Measuring The Battery's State Of Charge (Soc)And Balancing The Battery Cells Is One Of The Biggest Hurdles. There Has Been Substantial Research Devoted To The Design And Modeling Of Battery Management Systems (Bmss) Tailored For Electric Vehicles (Evs). Nevertheless, Prevailing Bms Architectures Typically Comprise Numerous Discrete Components, Highlighting The Necessity For Novel Integrated Designs That Consolidate Multiple Functions Within A Singular Unit. As Such, In This Thesis, A Bms Model, Developed For Electric Vehicle Applications Using Matlab Simulink Based On The Specifications Of Bmw I3 94 Ah Battery, Was Subjected To Testing Under Two Distinct Scenarios To Evaluate Its Performance. In The First Scenario, All Battery Cells Were Initialized At 100% Soc, Simulating An Ideal Condition. Conversely, The Second Scenario Involved Replicating A More Realistic Situation Where The Cells At 100%, 80%, And 74% Soc Were Selected. The Simulation Was Limited To 4000 Seconds To Manage Computational Demand, As The Target Of The Analysis Were Monitoring Of Battery State, Estimation Of State Of Charge, And Cell Balancing. The Results Demonstrated That The Model Accurately Monitored Voltage And Current In Both Scenarios, And It Effectively Estimated The Soc. Additionally, The Passive Cell Balancing Circuit Performed Well In Balancing The Cells' Soc, Taking Approximately 25% Of The Run Time To Balance The Circuit In The Second Condition. These Findings Indicate That The Model Is Suitable For Monitoring The Voltage And Current Of Cells, Estimating Soc, And Balancing Cells.