考虑悬架和电机作动器的参数摄动和控制输入的高阶未建模不确定性,利用线性分式变换理论对已开发的车辆电动悬架系统进行混合不确定建模和仿真,并设计了μ综合控制器。仿真得到了主动悬架和被动悬架的频率和时间响应。结果表明,相比被动悬架,所设计的μ综合控制器对乘坐舒适性有很大的提升。μ分析表明,与基于主动悬架名义模型设计的Huc综合控制器相比,μ综合控制器可使闭环系统获得更好的鲁棒稳定性和鲁棒性能。
In view of the parameter perturbation and high-order un-modeled uncertainty of active suspension and its motor actuator, the theory of linear fractional transformation is applied to the setting up of mixed uncertainty model for the developed vehicle electric suspension with its μ synthesis controller designed. A simulation is conducted to compare the responses in both frequency and time domains of active and passive suspensions. The results show that the designed μ synthesis controller achieves significant enhancement in ride comfort compared with passiw suspension. Meanwhile,μ analysis indicates that μ synthesis controller ensures better robust stability and robust performance of closed-loop system in comparison with the Hac synthesis controller designed based on the nominal model for active suspension.