Diseño de un BMS para vehículo de Fórmula Student de la Universidad de La Laguna

Abstract

The purpose of this final degree project is the design of a first prototype of a battery management system to be used in the future in the electric vehicle that is being built by students from the University of La Laguna. The vehicle is being built within the FSULL dynamics project to compete against other vehicles in this category developed by other universities. The purpose of a battery management system is to try to optimize the amount of energy stored in a pack in addition to ensuring the integrity of the cells that make it up. To do this, it monitors the voltages of each of the series present, in order to make sure that each of them is within the safe voltage values declared by the cell manufacturer. To optimize the load, what it does is balance the voltages, that is, once the voltages are measured, it looks at the differences between each series, and if a serie has more voltage than normal, it balances it with respect to the others in different possible ways. , depending on the bms topology. In the case of this design, it is a passive battery management system, which means that the balancing is done by short-circuiting the series to be discharged with a resistance to transform the excess energy into heat. In addition, its structure is such that you can have as many series as you want because it is based on modules capable of monitoring up to 12 series that communicate with a master via CAN bus, which makes it completely modular. External power is not required as the slaves are fed directly from the pack that balances. However the master must be powered via a low voltage battery up to 24V.