最优控制的汽车半主动悬架权重系数的研究

Research on Optimal Control of Automotive Semi-active Suspension Weight Coefficient

汽车行驶平顺性和操作稳定性与悬架有关参数关联密切。为提高半主动悬架性能,文章分别建立1/4车辆二自由度的被动悬架模型和半主动悬架模型,将二次型最优控制应用在半主动悬架上。采用MATLAB搭建仿真模型,通过调节最优控制中的权重系数,探究在同一随机路面上半主动悬架的车身垂直加速度、悬架动挠度、轮胎动载荷相对于被动悬架的变化情况。筛选出合适的权重系数,权重系数在一定变化范围内的半主动悬架的各方面性能优于被动悬架,并且可以调节其中一项权重系数而使悬架的某一项性能远远高于被动悬架甚至主动悬架。

The car ride comfort and operation stability are closely related to the suspension parameters.In order to improve the performance of semi-active suspension,the passive suspension model and semi-active suspension model of 1/4 vehicle with two degrees of freedom are established respectively in this paper,and the quadratic optimal control is applied to the semi-active suspension.MATLAB is used to build a simulation model.By adjusting the weight coefficient in the optimal control,the changes of the body vertical acceleration,suspension dynamic deflection and tire dynamic load of the semi-active suspension on the same random road surface are explored relative to the passive suspension.The appropriate weight coefficient is selected,and the performance of the semi-active suspension is better than that of the passive suspension in all aspects when the weight coefficient is within the range of its variation,and one of the weight coefficients can be adjusted so that the performance of one of the suspension is much higher than that of the passive suspension or even the active suspension.