Study on air-fuel ratio control of electronically-controlled engines
Accurate control of the air-fuel ratio is the most pivotal technology in modern automotive gasoline engine control. Most electronically-controlled gasoline engines run under conditions of partial load. Researching the air-fuel ratio control system of electronically-controlled engines under partial load condition is thus of great significance for reducing emissions and improving fuel economy. In this paper, after analyzing the target air-fuel ratio control, a mathematical model of the engine is first established. Then, air-fuel ratio PID control system is designed under the partial load condition, and the simulation model of the engine air-fuel ratio control is established. Finally, the control effect of the air-fuel ratio was compared with the conventional control system which didn't utilize the control strategy. Simulation results show that under partial load conditions, when using the PID algorithm, the control effect is better, control accuracy is higher, and the control performance is optimal.