Innovative hybrid-eco bus: Control strategies for reducing fuel consumption

In recent years the interest for electric vehicles is strongly growing. Together with the spreading of private electric vehicles also public transports are using electric buses. Series hybrid buses are often a good choice for reducing pollution, consumptions and to allow short tracks in pure electric mode. In this paper a series hybrid electric bus is described. The bus, realized in the framework of a project financed by the Italian Ministry of Economic Development, is a 12 meters public city bus. For this vehicle the innovation of connecting the storage system directly on the DC bus has been performed. This choice implies the necessity of studying proper control strategies in order to decouple the traction power from the generated power and to increase the efficiency of the diesel generator onboard. In this paper some control strategies are proposed and the results are analyzed by means of numerical simulation.