In this paper, an optimization algorithm based on modeling and simulation is proposed for torque and power optimization in automobile powertrain. Firstly, a complete mathematical model of power transmission system including engine, transmission, transmission shaft and driving wheel is constructed, including quasi-static model of engine, transmission ratio model of transmission, dynamic model of driving wheel and longitudinal dynamic equation of vehicle. On this basis, with the objective function of minimizing fuel consumption, combined with the constraints of engine working area, transmission gear logic, transmission shaft safety and power performance, a genetic algorithm is designed to optimize. The algorithm adopts mixed coding scheme, and realizes global optimization through genetic operations such as tournament selection, simulated binary crossover and polynomial mutation. The simulation analysis selects three typical scenarios: urban road condition, highway cruising condition and rapid acceleration overtaking condition. The results show that the fuel saving rate of the optimized urban condition is 14.9%, the fuel saving rate of the high-speed condition is 8.1%, and the transient fuel consumption of the rapid acceleration condition is reduced by 7.2%. At the same time, the optimization strategy significantly improves the shift smoothness and torque distribution stability, verifies the effectiveness of the algorithm, and provides theoretical basis and practical guidance for improving the performance of automobile powertrain.
Hou et al. (Sun,) studied this question.