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In hybrid electric vehicles (HEV), the operation strategy strongly influences the available system power, as well as local exhaust emissions. Predictive operation strategies rely on knowledge of future traction-force demands. This predicted information can be used to balance the battery’s state of charge or the engine’s thermal system in their legal operation limits and can reduce peak loads. Assuming the air and rolling drag-coefficient to be constant, the desired vehicle velocity, vehicle-mass and longitudinal driving resistances determine the vehicle’s traction-force demand. In this paper, a novel methodology, combining a history-based prediction algorithm for estimating future traction-force demands with the parameter identification of road grade angle and vehicle mass, is proposed. It is solely based on a route-history database and internal vehicle data, available on its on-board communication and measuring systems.

These days a new generation of hybrid electric vehicles (HEV) are penetrating the global vehicle market - the plug-in hybrid electric vehicles (PHEVs). Compared to conventional HEVs, PHEVs have additional significant potential. They are able to improve fuel efficiency and reduce local emissions due to higher battery capacities, and they can be recharged from external outlets. Energy management has a major impact on the PHEVs performance. In this publication, an innovative operation strategy for PHEVs is presented. This is due to the fact that both increasing fuel efficiency and enhancing the vehicle's longitudinal performance requires a fine balance between the consumption of fossil and electric energy. The new operation strategy combines advanced predictive and adaptive algorithms. In contrast to the charge-sustaining strategy of HEVs, the charge-depleting mode for PHEVs is more appropriate.

As the age of crude oil gradually finishes and political arrangements all over the world force a continuous reduction of global carbon dioxide (CO₂) emissions, energy efficiency and energy sustainability become worldwide a major challenge for automotive industry. The ambitious European goal of a fleet average emission for all new cars of 130 g/km CO₂ by 2012 afford an overall energy efficiency increase of the entire powertrain topologies. One way to come up to this challenge is surely the electrification of powertrain systems. Nowadays, hybrid electric vehicles (HEV) represent one of the most promising technologies that combine the advantages of high performance, high fuel efficiency and low emissions in combination with a long operating range. In literature exists lots of investigations concerning the requirements of different powertrain topologies along with the corresponding individual requirements of electric motor types.