A Modular Power and Energy Management Structure for Dual-Energy Source Electric Vehicles

This paper presents a modular approach to the design and implementation of a power and energy management system (PEMS) for electric vehicles (EV). The model EV is powered by dual energy sources, consisting of batteries and ultracapacitors. Operation of the PEMS has been structured into modular hierarchical process shells. The energy management shell (EMS) handles the longer-term decisions of energy usage in relation to the longitudinal dynamics of the vehicle. The process within the power management shell (PMS) however handles the fast decisions to generate power split ratios between the batteries and ultracapacitors. Finally the power electronics shell (PES) handles the ultra fast switching functions that facilitate the active power sharing between the two sources. Within the EMS, we employ a fuzzy inference system (FIS) as an intelligent decision engine. Simulations are presented to exemplify the function of the PMS and EMS. The modular structure approach is design-implementation oriented, with the objective of contributing towards a more unified description of EV power and energy management