Vehicle subsystems’ energy losses and model-based approach for fuel efficiency estimation towards an integrated optimisation

Improvement of passenger cars’ energy efficiency has nowadays become crucial for automotive companies. Vehicle energy loss assessment requires experimental procedures; the process is time consuming and expensive, thus virtual methods have been increasingly employed during design process. Model-based approaches have been widely used in vehicle subsystems and components design, however current methodologies focus on specific areas while few attempts to cover the entire vehicle system have been proposed. In this paper vehicle subsystems energy losses are analysed through a comprehensive literature review, simple models are then presented to evaluate subsystems’ steady-state performances and efficiency. The different modules are then coupled to simulate the entire vehicle behaviour while facing different driving scenarios and allowing to assess fuel economy and to evaluate the effect of design variations and new technologies.