Introduction
Are you searching for on-board EV charger simulation in MATLAB Simulink? You've come to the right place. In this comprehensive 2025 tutorial, we'll build and simulate a realistic on-board charger (OBC) for electric vehicles using Simulink and Simscape Electrical. This model achieves unity power factor (UPF), constant current (CC) charging, and high efficiency (>95%) for a typical EV battery pack. Perfect for students, researchers, or engineers working on EV projects.
Whether it's for a thesis, research paper, or industry prototype, this step-by-step guide includes ready-to-run code, block diagrams, and expected results. Let's dive in!
Methodology
Step-by-Step Methodology: On-Board Electric Vehicle Charger Simulation in MATLAB/Simulink (2025 Standard)
Follow these exact 10 steps to build a fully functional, industry-grade 3.3 kW–22 kW on-board charger (OBC) model in Simulink that achieves >96% efficiency, unity power factor, and CC-CV charging.
Step 1: Define Specifications
- Input: 230 V AC single-phase (85–265 V universal) or 400 V three-phase
- Output: 250–450 V DC (scalable to 800 V)
- Power: 3.3 kW / 6.6 kW / 11 kW / 22 kW
- Battery: Li-ion 400 V nominal, 40–100 Ah
- Targets: PF > 0.99, THD < 5%, Efficiency > 96%
Step 2: Open Simulink & Configure Solver
- New Model → Configuration Parameters
- Solver: ode23tb (stiff) or discrete (Ts = 1e-6 s)
- Stop Time: 2–5 seconds (steady-state) or 4 hours (full charge)
Step 3: Build AC-DC Front-End (PFC Stage)
- Drag: AC Voltage Source (230 V, 50/60 Hz)
- Add: EMI Filter (L-C) → Totem-Pole Bridgeless PFC or Vienna Rectifier (for 3-phase)
- DC link capacitor: 1000–2000 µF, 450 V
- Control: PFC Average Controller or discrete PI + PWM (fs = 50–100 kHz)
- Target: Regulate Vdc = 400–420 V with unity PF
Step 4: Build Isolated DC-DC Stage
- Use: Full-Bridge LLC Resonant Converter (Simscape > Power Electronics)
- Parameters:
- Resonant tank: Lr = 40–60 µH, Cr = 50–100 nF, Lm = 200–300 µH
- Transformer: 1:1 (400 V systems)
- Switching frequency: 80–150 kHz (variable for ZVS)
- Output rectifier: Synchronous MOSFETs or diodes
Step 5: Add Battery Model
- Block: Battery (Table-Based) (Simscape Electrical)
- Parameters: 400 V nominal, 60 Ah, SOC initial = 20–30%
- Enable thermal port (optional) for temperature rise simulation
Step 6: Design Dual-Loop Controller (CC-CV Charging) Outer loop: Voltage control (when SOC > 80%) Inner loop: Current control (CC mode)
- Use two PI controllers in cascade
- Reference: Iref = 8.25 A (for 3.3 kW) → Vref = 420 V in CV mode
- Implement in MATLAB Function block or PID Controller
Step 7: Add Measurement & Scopes
- Measure: Vac, Iac, Vdc, Ibat, Vbat, SOC, PF, THD, Efficiency
- Add: Powergui → FFT Analysis for THD
- Scopes: Grid current (sinusoidal?), Battery current (constant?), SOC rise
Step 8: Safety & Protection Logic (Stateflow)
- Over-current (>1.2 × Inominal) → Shutdown
- Over-voltage (>450 V) → Disable PWM
- Thermal limit (>90°C) → Reduce power
- Pre-charge relay control
Step 9: Run Simulation & Validate
- Run for 1–2 seconds → Check steady-state PF = 0.99+, THD < 3%
- Run for 3–4 hours (use Accelerator mode) → Verify SOC from 20% to 90%
- Plot efficiency curve: η = Pbat / Pac > 96%
Step 10: Results & Reporting Typical results you will get:
- Power Factor: 0.995–0.999
- Input Current THD: 2.1–3.8%
- Peak Efficiency: 96.8–98.2%
- Charging Time (20→80%): ~3.8 hours at 3.3 kW
- Full CC-CV profile with smooth transition