四缸汽油发动机点火正时控制策略与仿真研究

Ignition Timing Control Strategy and Simulation Research on Four Cylinder Gasoline Engine

以某型汽油发动机为原型机,在GT-Power软件中搭建仿真模型.仿真结果表明,仿真模型在输出功率、力矩上与原型机误差在3%以内.以该模型为基准,仿真分析点火提前角对输出功率、力矩的影响,以及不同工况对发动机输出性能的影响.并以输出力矩为优化目标,以输出力矩变化量、上一采样时刻点火提前角变化量为模糊控制算法输入,以当前点火提前角变化量为模糊控制算法输出,采用模糊控制算法寻找输出力矩极大值点的点火提前角.采用GT-Power和Simulink联合仿真,仿真实验结果表明,该控制策略修正了点火提前角,提高了发动机的输出力矩,且具有快速、稳定、精度高的特性.

A gasoline engine is used as a prototype,and a simulation model is built in GT-Power. The simulation results show that the simulation model has less than 3% error in the output power and torque compared with the prototype. Based on the model,the influence of ignition advance angle on the output power and torque is simulated and analyzed,and the influence of different working conditions on the output performance of the engine is simulated and analyzed. The output torque is used as the optimization target,and meanwhile the output torque change amount and the ignition advance angle change amount at the last sampling time are used as the fuzzy control algorithm input. The current ignition advance angle change amount is used as the fuzzy control algorithm output,and the fuzzy control algorithm is used to find the ignition advance angle of the output torque max point. The GT-Power and Simulink joint simulation results show that the control strategy modifies the ignition advance angle,improves the output torque of the engine,and has the characteristics of being fast,stable and highly precise.