Development of battery management system and investigation of canbus data traffic

Recently, the use and production of electric vehicles has been increasing. In parallel with this increase, electric vehicle technologies are constantly developing. With the increase in the use of electric vehicles, the importance of BMS (Battery Management System), which controls the charge and discharge cycles of batteries, is increasing and researches are being carried out to increase their efficiency. Batteries with high energy density used in electric vehicles need to be kept under constant control. A large number of cells are used to obtain the high voltage and capacity required by electric vehicles. Each cell needs a battery management system to keep it under control. CAN (Controller Area Network) is used in BMS communication with the vehicle. In this thesis, the data traffic on the CAN line of the BMS used in today's electric vehicles has been analyzed. In this analysis, instant data of the battery pack is sent over the CAN line. The system includes BMS, charger and VCU (Vehicle Control Unit). An experimental setup with BMS, VCU and charger nodes was prepared and line load calculation was made on this experimental setup. Three different methods were used in the line load calculation process and the relationship of these methods with each other was compared. Different CAN speeds were used in the test stages and line load analysis was performed by changing the message sending frequencies. According to the data obtained from the prepared experimental setup, it was seen that the load of the messages on the CAN line was between 1.97% and 19.58%.