Development of a novel Energy Management Strategy for Hybrid Electric Vehicles

Nowadays, in order to provide high efficiency products, automotive industry is looking towards Hybrid Electric Vehicles. Fuel Cells technology is considered to be a promising solution for on board power generation. However, FCs require auxiliary sources, such as Batteries and/or Ultracapacitors, in order to deal with the issue of fast load dynamics. Within that context, Energy Management Strategy is defined as a critical component of Hybrid Electric Vehicle, since it is responsible for energy sharing among the different sources. In this paper, a novel Energy Management Strategy is proposed that aims on current sharing between primary and auxiliary sources. This strategy is deployed in two stages through a set of rate limiter and a Fuzzy Logic Controller. The first stage defines the low harmonic component of current load demand and assigns it to FC, while the second determines which harmonic component of current load demand Ultracapacitor should cover. That procedure takes considerably into consideration energy stored in ancillary sources as well as load demands. Simulation results validate the efficiency of the proposed Energy Management Strategy.