Battery Management System Software for a High Voltage Battery Pack

Abstract: The electric vehicle industry is experiencing a boom infunding and public interest, and the formula student movementis following suit; an electric race car is currently being developedby the KTH Formula Student organisation (KTHFS) which is thecause of this work.Consumers desire increased speed and range, and are unwillingto compromise one quality for the other. This necessitates the useof lithium ion cells, which may explode and exhume toxic gasesif over-strained with respect to current, charge or temperature.A robust, reliable and provably safe battery management systemshould therefore be developed. There are numerous methods tofurther increase the mileage to get an edge on competitors, suchas cell balancing and live estimation of the State of Charge(SOC). It is also vital that old and/or deteriorated cells should beidentified and disposed off in due time, and State of health (SOH)estimation provides a means to do this. In this paper a completebattery management system software solution is developed andpresented, utilising methods like simulation and code generationto create a program that runs on a real time operating system(RTOS). Some real world test were conducted and some resultsare simulated. The finished BMS performed well in tests, meets allgoals and meets all timing constraints. The project can thereforebe considered as successful.