The Design and Simulation of Fuzzy Logic Controller for Parallel Hybrid Electric Vehicles

In this paper, the fuzzy logic controller for a parallel hybrid electric vehicle is proposed. The required torque for deriving in parallel hybrid vehicle is generated by a combination of internal-combustion engine and an electric motor. The fuzzy logic controller was designed based on the state of charge of batteries and the desired torque for driving. The output of the controller actually controls the throttle angle degree of the internal-combustion engine in order to make it work in a high efficiency region. The electronic motor works as an auxiliary power, it is sized to supply peak power to meet the load power requirement of the vehicle. The result of simulation shows the excellent effect of the optimal control strategy can share the required power between internal-combustion engine and electric motor properly. Through the simulation, it can be proved that the fuzzy logic controller is useful for the improvement of driving performance and the fuzzy logical technique is suitable for hybrid electric vehicles, it also makes the hybrid vehicles achieve good fuel economy and low emissions performance.