Hierarchical switch control for ISG-HEVs

Abstract

To overcome the shortcomings of the micro integrated starter/generator (ISG) and the mild ISG, this paper designs a novel ISG-HEV (Hybrid Electric Vehicle) that contains three kinds of hybrid propulsion modes: micro, mild, full. Firstly, the mode switch is divided into two layers to reduce the complexity of control algorithm. Then, the division of the working modes and the electric driving modes are constructed respectively. Lastly, the control strategy designed is simulated from the switch of working modes, the change of the electrical system power ratio λ and part performances of the internal combustion engine (ICE), the ISG, the electric motor/generator (EMG) and batteries in ADVISOR. The results show that the control strategy presented can ensure the good fuel economy on the basis of the satisfactory dynamic performance, meanwhile, maintain battery SOC within its operation range.