These days, at the beginning of the 21st century, scientific breakthroughs in the fields of technology and electronics makes it seem like the days of widespread use of electrical-powered cars are upon us. The only factor that limits their popularity is the disparity between the time that is needed to charge a battery and the time that is needed to refuel a car with an internal combustion engine. A lot of research is going into this field of electronics right now, to solve the issue of charging the batteries of these cars.
The topic of my thesis relates to the BME-MOTION university group’s efforts towards creating a battery powered racecar with a hub motor and voltage source inverter. I will deal with design of the power and control circuits of a portable fast-charger.
In the first section, after a short introduction, I will review the LiFePO4-type batteries’ charging methods, and will propose the most practical one. These batteries are used in the racecar of the university group. Then I give a short specification for the battery fast-charger.
The battery pack of the race car and its charging circuit is a high-voltage system. Therefore, special attention should be paid to safety and protection. In the second section of my thesis, after a short review of the – previously manufactured – power electronics stage, I will survey, choose and size the protection circuits to meet safety requirements.
The third section is given over to the design of control and driver circuits. The main scope of my task is design and realization of voltage and current control, as well as protection circuits and IGBT drivers. I will theoretically check and practically test the correct functioning of the ready-made modules.
The fourth chapter of my thesis will present the results of tests and theoretical investigations. On the base of analysis of test results, I will make a proposal for further developments.