Design of auxiliary battery management system and energyefficiency optimization in commercial electric vehicle superstructure transformation

In recent years, there has been a significant increase in global demand for sustainable transportation solutions. Electric vehicles (EV) stand out as one of the most important alternatives in this field due to their low carbon emissions and environmentally friendly nature. However, the conversion of N2 class electric panel vans into M2 class service and school vehicles presents a major challenge due to energy insufficiency. The current high-voltage batteries are inadequate to meet the energy demands of essential systems such as air conditioning, heating, electric steps, sliding doors, USB devices, and lighting systems in M2 class vehicles To overcome this issue, it is necessary to strengthen the energy infrastructure with an additional battery and charging control system integrated into the vehicle. This integration enhances the battery infrastructure of electric vehicles, ensuring the energy supply for the necessary systems. In this thesis study, an additional battery management system providing the necessary energy for the superstructure conversion of an N2-class electric vehicle was integrated into the vehicle. The vehicle was then converted into an M2-class electric vehicle, completing the superstructure conversion. A 48V, 5.4 kWh battery integration and a 3.5 kW On-Board Charger (OBC) were designed and integrated into the vehicle. The battery was placed inside the base under the hostess seat to meet the vehicle's carrying capacity and range requirements. Additionally, real measurement data were obtained from an internal combustion vehicle, demonstrating that the converted electric vehicle, with its additional battery management system, achieved energy efficiency compared to internal combustion vehicles. With the proper design and integration of these systems, N2 class electric panel vans can be successfully converted into M2 class service and school vehicles. This integration supports the upper structure transformation of electric vehicles, contributing to the widespread adoption of environmentally friendly and energy-efficient transportation solutions. This transformation, especially aimed at enhancing energy efficiency and sustainability in school and service vehicles, will lead to the development of more sustainable transportation alternatives in the future.