Energy balance based verification for hybrid vehicle models

Recently, automobile industry requires energy saving technology for reducing the environment burden and operational costs. Hybrid engines are environmental friendly, but hybrid heavy-duty trucks have not been still sold in the Japanese market, as their development has posed considerable problems. To solve these problems, the automobile industry has begun to develop simulation models of actual vehicles. Nevertheless, at the moment, the simulators are still unreliable and the developers cannot obtain accurate results. Compared to automobiles with combustion engines, the recent hybridization complicates the verification of the simulation results, because a hybrid vehicle is a complex system composed of mechanical systems, electric systems, control units and so on. Motivated by this, this paper shows a new verification method which focuses on the energy balance between the various components. Since the energy conservation law holds for both the mechanical systems and the electric systems, our proposed method allows us to verify complex models like hybrid vehicles. In this paper, a mathematical model for a hybrid heavy-duty truck is developed and the approach based on energy balance is verified.