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Comparative analysis of the proposed charging method to the existing charging methods_
| Parameter | Existing charging systems | Proposed adaptive charging system | Reference(s) |
|---|---|---|---|
| Charging mode | Fixed CC/CV | Adaptive CC–CV with SOC and temperature feedback | Zdraveski et al. (2022), Etemesi et al. (2024) and Balasundar et al. (2021) |
| Charging power | 7–10 kW | 12 kW | Sethuraman and Rudhramoorthy (2024), Rivera et al. (2021) and Pradhan et al. (2023) |
| Charging time (20%–80% SOC) | 6.5–8 h | 5 h (reduced by 30%) | Hammerschmitt et al. (2024), Pradhan et al. (2023) and Rivera et al. (2021) |
| THD (grid current—G2V) | 4%–5% | 1.33% | Balasundar et al. (2021) and IEEE Standards Association (2014) |
| THD (grid current—V2G) | 4.5%–5% | 1.7% | Balasundar et al. (2021) and IEEE Standards Association (2014) |
| Control strategy | Fixed PI control without real-time adaptation | Adaptive controller with real-time SOC & temperature feedback | Etemesi et al. (2024) |
| Thermal management | Passive or external cooling-based cut-off | Real-time thermal model with current derating | Shahjalal et al. (2021) |
| Battery stress | High during fast charging (no thermal limit) | Reduced due to derating and smooth mode transitions | Zdraveski et al. (2022) and Etemesi et al. (2024) |
| Grid compliance | Limited harmonic mitigation | Enhanced via LCL filter | Han et al. (2020) and Balasundar et al. (2021) |
| Bidirectional operation (V2G) | Limited or not supported | Fully supported with control reversibility | Bera et al. (2022) |
| Charging efficiency | 88%–95% | 98.3% | Han et al. (2020) and Rivera et al. (2021) |
| Battery life span | Degrades with uncontrolled fast charging | Improved | Pradhan et al. (2023) and Levek and Steffan (2019) |
Parameters of the system_
| Parameter | Value |
|---|---|
| Grid voltage | 325 V |
| Grid current | 25 A |
| Grid frequency | 50 Hz |
| Switching frequency | 10 kHz |
| DC-link voltage | 800 V |
| LCL filter inductance (each side) | 5 mH |
| LCL filter capacitance | 30 µF |
| DC link capacitance | 5,600 µF |
Battery specifications_
| Parameter | Value |
|---|---|
| Battery rated voltage | 415 V |
| Maximum charging current | 30 A |
| Rated capacity | 50 kWh |
| Initial SOC | 20% |
| SOC threshold (CC CV) | 80% |
| Internal battery resistance | 0.1 Ω |
| Temperature limit | 45°C |
Sensitivity analysis with parameter variation_
| Parameter | Variation | THD (G2V) | THD (V2G) |
|---|---|---|---|
| Lg (mH) | 4.5–5.5 (±10% change in grid side inductance) | 1.23%–1.51% | 1.62%–2.1% |
| Grid voltage (V) | 370–460 V (±10% change in grid voltage) | 1.27%–1.48% | 1.65%–1.92% |