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The development of an energy management system for a fuel cell hybrid electric vehicle (FCHEV) based on single step dynamic programming (SSDP) is described in this paper. The SSDP method is used to minimize a weighted cost of hydrogen and battery degradation with the latter being controlled to carry out charge-depleting (CD) as well as charge-sustaining (CS) strategies with simple lower bound enforcement or relaxation. The problem formulation accounts for the power balance at each stage, the fuel cell and battery power limits, the battery state-of-charge limits, and the ramp-rates constraints of the fuel cell and battery. Its chief advantage over forward dynamic programming (DP) or other formal optimization methods is that it does not require the speed forecast of the whole drive cycle but requires only a one-step-ahead speed forecast.

Long-term rise of oil prices, increasingly stringent emission regulations, combined with emerging regulations to reduce truck engine idling present a unique opportunity for hybrid trucks. Tutto Industria de Sistemas de Tracao Electrica is a Brazilian Company located in Caxias do Sul which is dedicated to develop and commercialize electric and hybrid drive trains for commercial vehicles. In this paper a case study for a Brazilian delivery truck application will be presented. First the fundamental architecture of a series hybrid delivery truck is described and simulation models for a conventional 8 t delivery truck and the responsive hybrid electric truck are built, and serve as a basis for powertrain components and control strategy analysis. Comparisons of the hybrid truck with the conventional truck are performed, and important factors relating to the vehicle performance (gross vehicle weight, drive cycles, control strategies) are investigated.

A hybrid electric vehicle simulation tool (IBZ-Simulator) has been developed at the Fuel Cell Institute of the University of Applied Sciences Esslingen to study the fuel economy potential of a Fuel Cell hybrid urban bus. In this paper, the fundamental architecture of the FC urban buses was described, as well as the control strategy to manage the power flow between the different elements of the drive train. A comparison of the hybrid with the conventional type and ICE-hybrid type is performed, and important factors relating to the vehicle efficiency (accessory loads, vehicle mass, Fuel Cell system ramping rate and battery capacity) were assessed. The using of supercapacitor (or ultracapacitors) as peak power buffer has been investigated.