A Comparative Study and Analysis of an Optimized Control Strategy for the Toyota Hybrid System

The Toyota Prius equipped with the Toyota Hybrid System (THS) II vehicle uses a combination of a combustion engine and two electric machines in order to increase the efficiency and the fuel economy. The Energy Management Strategy (EMS) of the THS II is analyzed using measurement data collected with a Toyota Prius under different driving conditions on the road and compared with an optimized EMS based on simulations. The main goal of this paper is to verify the control strategy as implemented in the Prius by comparing the measured strategy with an optimized strategy based on Energy Consumption Minimization Strategy (ECMS). The differences between the simulation results and the actual measured strategy are analysed and discussed.