Fuzzy controller design for parallel hybrid vehicle analysis using forward simulation

In order to convert conventional vehicles to their hybrid counterparts, trustworthy simulation with driving realities are essential. Here, a seven-degree-of-freedom model is developed to simulate the dynamical behavior of vehicles. Next, by modeling the components engine, gear box, clutch, differential, electrical machine, and battery (look up table), the hybrid automobile is modeled. In this way, forward simulation of vehicle from pedals to wheels power transformation is accomplished. Consequently, various effective forces in vehicle fuel consumption are considered such as aerodynamics and friction forces. Then, a fuzzy controller using proper rule base is designed which is shown to be completely capable of improving the fuel economy and regenerative braking. In addition, electrical machine power is obtained by a fuzzy controller based on battery state of charge and estimated engine power. Finally, effectiveness of the proposed structure is confirmed by a series of MATLAB/SIMULINK simulation results.