Development of a compact regenerative braking system for electric vehicles

In this paper, a detailed study and implementation of a reliable and efficient regenerative braking system is presented. It is applied on a prototype electric vehicle, that uses a hydrogen fuel cell as its only power source. Supercapacitors are used to store the energy that is generated during braking, transistors for switching the alternative circuits and an embedded computer controller program undertakes the synchronization of the system tasks. A finite state machine was designed to create a simple but robust technique to control the transistor switches according to the system´s sensory inputs. The system is powered by its own supercapacitors, and thus it may be used in a plug-and-play manner. On-road test drives proved the system´s reliability and efficiency.