Electric Vehicle & Hybrid Electric Vehicle (EV/HEV) MATLAB & Simulink Models

This repository contains MATLAB scripts and Simulink models developed and studied during the Instructor-Led Training (ILT) sessions delivered by L&T EduTech.

These sessions were conducted at Sikkim Manipal Institute of Technology (SMIT), jointly organized by the Department of Electrical & Electronics Engineering (EEE) and the Department of Mechanical Engineering (ME) as part of the Minor Specialization in Electric Vehicles and Hybrid Electric Vehicles (EV/HEV) in collaboration with L&T EduTech.

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📋 Table of Contents

• Overview
• Repository Structure
• Models & Simulations
  • 1. EV Tractive Effort & Vehicle Dynamics
  • 2. BLDC Motor Back-EMF Model
  • 3. Three-Phase Inverter Model
  • 4. Single Cell Battery Charging Model
  • 5. Battery Management System (BMS)
• Governing Mathematical Equations
• Default Vehicle Parameters
• Prerequisites & Getting Started
• Academic & Industry Acknowledgments
• Author & License

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⚡ Overview

The transition towards e-mobility requires multidisciplinary understanding bridging electrical machine drives, power electronics, and mechanical vehicle dynamics. This repository hosts simulation models focused on:

• Longitudinal vehicle dynamics and tractive force requirements.
• Sizing and power demand estimations for electric powertrains across variable drive speeds.
• Back-EMF characterization of Brushless DC (BLDC) motors.
• Three-phase inverter modeling and electronic switching dynamics for BLDC drives.
• Single-cell Lithium-ion battery charging simulation (constant current to 100% SOC).
• Battery Management System (BMS) monitoring dashboard with SOC estimation, voltage and current tracking, and fault protection warnings.

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📁 Repository Structure

EV_Engineering_Models/
├── .gitignore                          # Ignored files (.DS_Store, MATLAB autosaves, cache)
├── assets/
│   ├── Hero banner.png                 # README header banner image
│   └── Screenshots/
│       ├── Aerodynamic Drag.png        # Aerodynamic drag calculation block subsystem
│       ├── Ang Speed Three Phase Inverter.png # Angular velocity waveform of three-phase inverter drive
│       ├── BLDC Back EMF.png           # BLDC Back-EMF Simulink model architecture
│       ├── BLDC Graph.png              # BLDC Back-EMF scope waveform
│       ├── BMS.png                     # BMS Monitoring Dashboard architecture & indicators
│       ├── Grade Force.png             # Grade force calculation block subsystem
│       ├── Inertial Force.png          # Inertial force calculation block subsystem
│       ├── Rolling Resistance.png      # Rolling resistance calculation block subsystem
│       ├── Single Cell Charging.png    # Single-cell charging model architecture
│       ├── Speed Three Phase Inverter.png # Angular position theta waveform of three-phase inverter drive
│       ├── Three Phase Inverter.png    # Three-Phase Inverter Simulink model architecture
│       └── Total Tractive Force.png    # Total tractive force summation block diagram
├── models/
│   ├── BLDC_Back_EMF.slx               # Simulink model for BLDC Motor Back-EMF simulation
│   ├── BMS.slx                         # Simulink model for Battery Management System dashboard
│   ├── EV_Tractive_Effort_Model.slx    # Simulink model for EV Tractive Effort calculation
│   ├── Modeling_three_phase_inverter.slx # Simulink model for Three-Phase Inverter driving BLDC
│   ├── Single_Cell_Charging.slx        # Simulink model for Single-Cell Li-ion battery charging
│   └── Tractive_Effort_Simulation.m    # MATLAB script computing tractive forces & power vs speed
├── LICENSE                             # MIT License
└── README.md                           # Project documentation

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🚗 Models & Simulations

1. EV Tractive Effort & Vehicle Dynamics

• Files: Tractive_Effort_Simulation.m, EV_Tractive_Effort_Model.slx
• Description: Evaluates the resistance forces opposing vehicle motion (rolling resistance, aerodynamic drag, grade resistance, and acceleration force) over a speed range of $0$ to $150 \text{ km/h}$. Computes total tractive effort and required motor mechanical power output.

Simulink Model Architecture & Subsystems:

Figure 1: Vehicle Total Tractive Force summation block diagram in Simulink

Figure 2: Rolling Resistance Force calculation subsystem

Figure 3: Aerodynamic Drag Force calculation subsystem

Figure 4: Grade Force calculation subsystem

Figure 5: Inertial Force calculation subsystem

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2. BLDC Motor Back-EMF Model

• File: BLDC_Back_EMF.slx
• Description: Models a Brushless DC (BLDC) motor driven by an ideal angular velocity source ($2\pi \text{ rad/s}$) to measure and characterize the induced trapezoidal Back Electromotive Force (Back-EMF). Evaluates the phase Back-EMF amplitude and profile critical for motor timing and electronic commutation logic.

Simulink Model Architecture:

Figure 6: BLDC Motor Back-EMF Simulink schematic with ideal angular velocity source

Scope Waveforms & Response:

Figure 7: Measured trapezoidal Back-EMF voltage waveform across the motor phase

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3. Three-Phase Inverter Model

• File: Modeling_three_phase_inverter.slx
• Description: Simulates a Three-Phase Inverter feeding a Brushless DC motor under a specified switching sequence ([1 0 0 0 0 1]). Analyzes the electro-mechanical transient response, capturing rotor speed oscillations and rotor angular displacement ($\theta$) settling to steady state.

Simulink Model Architecture:

Figure 8: Three-Phase Inverter Simulink schematic driving a BLDC motor

Dynamic Response & Waveforms:

Figure 9: Rotor angular velocity dynamic transient response

Figure 10: Rotor angular position ($\theta$) response settling over time

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4. Single Cell Battery Charging Model

• File: Single_Cell_Charging.slx
• Description: Models constant-current (CC) charging of an individual lithium-ion cell (Panasonic NCR18650BD) supplied by a controlled current source ($3.153 \text{ A}$). Monitors cell State of Charge (SOC) in real-time and automatically terminates simulation when the cell reaches $100%$ SOC ($1.0$).

Simulink Model Architecture:

Figure 11: Single-cell lithium-ion battery charging schematic with controlled current source and automatic stop logic

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5. Battery Management System (BMS)

• File: BMS.slx
• Description: Implements a comprehensive Battery Management System (BMS) monitoring dashboard. Tracks battery current and terminal voltage, integrates current for SOC tracking, computes estimation errors, and utilizes relational logic thresholds to trigger real-time indicators for Normal Operation, Overcharge Warning, and Low Battery Warning.

Simulink Model Architecture:

Figure 12: Battery Management System (BMS) monitoring dashboard schematic with operational status indicators

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📐 Governing Mathematical Equations

The total tractive effort ($F_{total}$) demanded by the vehicle to maintain acceleration and overcome resistive forces is given by:

$$F_{total} = F_{rr} + F_{d} + F_{grade} + F_{acc}$$

Where:

1. Rolling Resistance Force ($F_{rr}$): $$F_{rr} = C_{rr} \cdot m \cdot g \cdot \cos(\theta)$$

2. Aerodynamic Drag Force ($F_{d}$): $$F_{d} = \frac{1}{2} \cdot \rho \cdot C_d \cdot A \cdot v^2$$

3. Grade Resistance Force ($F_{grade}$): $$F_{grade} = m \cdot g \cdot \sin(\theta)$$

4. Acceleration Inertia Force ($F_{acc}$): $$F_{acc} = m \cdot a$$

5. Motor Power Requirement ($P$): $$P_{\text{kW}} = \frac{F_{total} \cdot v}{1000}$$

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📊 Default Vehicle Parameters

The parameters configured in Tractive_Effort_Simulation.m are:

Parameter	Symbol	Value	Unit
Vehicle Mass	$m$	$1200$	$\text{kg}$
Acceleration due to Gravity	$g$	$9.81$	$\text{m/s}^2$
Rolling Resistance Coefficient	$C_{rr}$	$0.012$	—
Air Density	$\rho$	$1.225$	$\text{kg/m}^3$
Aerodynamic Drag Coefficient	$C_d$	$0.29$	—
Frontal Area	$A$	$2.2$	$\text{m}^2$
Road Grade Angle	$\theta$	$0$	$\text{degrees}$
Vehicle Acceleration	$a$	$2.0$	$\text{m/s}^2$
Speed Range	$v$	$0 - 150$	$\text{km/h}$

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🚀 Prerequisites & Getting Started

Prerequisites

• MATLAB (R2021a or newer recommended)
• Simulink
• Simscape / Simscape Electrical (for motor drive and physical modeling blocks)
• Powertrain Blockset (optional, recommended)

Running the Tractive Effort Script

1. Open MATLAB and set the current working directory to this repository.
2. Run the simulation script:

   run('models/Tractive_Effort_Simulation.m')

3. View the console output table of speed vs. force/power and the three generated figure windows.

Running Simulink Models

1. In the MATLAB command window, type any of the following to open a model:

   open('models/EV_Tractive_Effort_Model.slx')
   open('models/BLDC_Back_EMF.slx')
   open('models/Modeling_three_phase_inverter.slx')
   open('models/Single_Cell_Charging.slx')
   open('models/BMS.slx')

2. Click Run on the Simulink toolstrip to simulate the response over the designated time horizon.
3. Open the Scope or Display blocks to observe torque, speed, phase waveforms, or BMS dashboard metrics.

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🎓 Academic & Industry Acknowledgments

This work is part of the Minor Specialization in Electric Vehicles and Hybrid Vehicles:

• Industry Partner: L&T EduTech (Larsen & Toubro)
• Institution: Sikkim Manipal Institute of Technology (SMIT), Sikkim Manipal University
• Departments:
  • Department of Electrical & Electronics Engineering (EEE)
  • Department of Mechanical Engineering (ME)
• Program: Instructor-Led Training (ILT) Sessions on EV Modeling & Simulation

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👤 Author & License

• Author: Krish Anand
• License: This project is licensed under the MIT License.