Optimal Torque Based Fuzzy Logic Control Strategy of Parallel Hybrid Electric Vehicle

Control strategy that determines the overall efficiency of hybrid system plays a centre role in hybrid electric vehicle (HEV). Utilizing fuzzy logic with quadratic programming, an optimal torque based fuzzy logic control strategy for parallel hybrid electric vehicle is built. The controller is designed based on battery state of charge, electric motor speed, and a relationship between the totally required torque and the optimal engine torque, which is calculated in advance through quadratic programming to better the designed strategy. The output of the controller is a coefficient, namely the electric throttle of motor which controls the torque of electric motor. For the purpose of achieving a better fuel economy, simulations are done with results that confirm the validity of the designed controller, which can be flexible to allow extension and reconfiguration.