Development of energy management strategy for plug-in hybrid city bus

This paper introduces simulation based development process of energy management strategy (EMS) for plug-in hybrid city bus. Based on a given driving cycle and operating schedule, theoretical control parameters are developed depending on the optimization target. Simulation is used for adjusting these parameters to make them suitable for a real-time control strategy. Different driving cycles are used during the development process for investigating the required initial data and technical complexity of the control strategy. Fuel consumption and battery aging minimization are used as optimization targets but also other targets can be defined. The simulation results show that plug-in hybrid city bus fuel consumption and battery aging are strongly dependent on the driving cycle. By optimizing fuel consumption alone, already a significant increase on battery life was observed. Battery life can be further improved by a compromise solution between fuel economy and battery aging.