Today we are experiencing an incresing number of electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV). They store energy in battery cells, which are then connected into battery packs. Electric vehicles are charged at charging stations installed in major cities and tourist destinations across Europe. Stations can charge with alternating or direct current. In both cases, communication between charging station and electric vehicle is very important. In this thesis i focus on communication between charging station and EV using alternating charging current. Circuit hardware and software are checking the frequency, amplitude and pulse width (PWM) send by charging station. The oscillator in station sends pulses with frequency 1 kHz and duty cycle between 10 and 90 percent. Depend on duty cycle, we calculate maximum current by which the vehicle can be charged. The calculated current is then send via CAN bus to the battery management system(BMS), which communicates with charger placed in the vehicle. Charging begins when the internal resistance is reduced between ground(PE) and communication (CP) line. This signal communiates with charging station that the vehicle is ready to accept energy and start charging.
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