汽车恒速下坡滑膜变结构控制的仿真研究

摘要

A great risk to the safety of driver and passengers is occurred if the automobile speed is unpredictable because of the great change to the road condition,so automobile downhill at constant speed has important significance for driving safety,in order to control automobile downhill at constant speed accurately,variable structure control strategy was applied based on variable structure theory,engine output torque was considered as controllingfunction.Aimed at certain type automobile ,the curve of automobile downhill at the speed of 30Km/h,relationship chart of engine output torque and influence diagram of road surface randomfluctuation to vehicle speed were obtained by Matlab/Simulink software simulation.According to the result, it shows that automobile speed can be controlled stability at the range of set value by variable structure control strategy,the controlled system has strong resistance to interference and better dynamic performance.%汽车车速因路况变化较大而存在的不可预测性对驾乘人员安全造成很大危险,为此汽车恒速下坡控制对行驶安全性有着重要意义.为精确控制汽车下坡车速,首先根据滑膜变结构原理,以发动机输出扭矩作为控制函数,设计了滑膜变结构控制策略.针对给定的某款车型,通过Matlab/Simulink仿真,得到汽车30Km/h车速下坡时的控制曲线图、发动机输出扭矩与车速关系图以及路面随机波动对车速影响图.仿真结果表明:滑膜变结构控制策略能使汽车下坡时车速稳定在设定值内,控制系统抗干扰性强,动态性能好.