ABSTRACT
Electric vehicles (EV) became one of the highest upcoming new technologies that received global recognition. The reasons are that fuel-based vehicles consume fossil fuels that are of limited availability and cause a massive negative impact on the environment. In the EV technologies, batteries and their charging are considered an essential part of the electric vehicles. As a result, the approach of battery charging is substantial, and its protection is indispensable.
In this project, an intelligent high-power On-Board Charger (OBC) for the electric vehicle’s battery is designed in a way that allows for a driver to charge the battery from a home-like AC power supply. Furthermore, the onboard charger is also intelligent such that it continuously provides information that can be used for real-time monitoring of the OBC status. The type of battery used here is Lithium-ion battery following some design constraints such as charging voltage and charging power, input current THD, and battery voltage, taking into consideration the IEEE standards of 519-2014. However, the charger is divided into multiple stages. In the first stage, one topology of charging will be used in which a rectifier is used followed by a boost converter and then a buck converter. Then, a control circuit will be added for the system to meet the requirements. The rectifier boost topology will be compared with another two converters (Ćuk & SEPIC), to show a comparison between them. The SEPIC converter is selected where designing and modeling of the SEPIC converter is done. This model will then be compared to the simulation of SEPIC using Simulink.
The input voltage is 240 V single phase, which can be fed from a standard AC power socket. Also, the battery rated voltage is 48V, which can be used for the low-speed electric vehicles, and the output power ranges between (4 to 6) kW with a switching frequency of 20kHz as minimum frequency. Furthermore, the full system is designed and then simulated using MATLAB/Simulink platform. The system is evaluated considering the design constraints. The practical testing will be conducted first the rectifier-boost-buck model, then will be developed for the rectifier-SEPIC model.