Rating of the Power Components in Series-hybrid Buses with Different Supply Control Strategies

The paper describes a methodology for the preliminary sizing and the analysis of the supply and propulsion systems in series-hybrid electric buses, consisting of a diesel-electric group supplying an electric motor. Starting from the evaluation of the load demand related to a predefined driving cycle, an analytical procedure is developed to find out the ratings of the power sources, consisting of a diesel-electric unit and a battery pack. Different control strategies are also examined in order to limit the battery stresses, to reduce the fuel consumptions and gas emissions and to ensure an adequate operating range. The results obtained in the example of application are used as input data for a simulation code to check the correctness of the proposed procedure and to investigate the vehicle performances by a parametric analysis