针对高速轨道车辆簧上质量、弹簧刚度的摄动问题,利用线性分式变换LFT对车辆垂向振动模型进行不确定分析,将模型中摄动参数隔离出来,并根据性能要求选择权函数设计鲁棒μ控制器。以轨道高低不平顺作为外部激励进行仿真,其控制效果与基于名义模型设计的鲁棒H∞控制器进行对比。仿真结果表明:仅存在外部扰动时,鲁棒H∞控制器表现出更优的控制效果;外部扰动和内部参数摄动同时存在时,鲁棒H∞控制器控制效果明显恶化,鲁棒μ控制器表现相对稳定。鲁棒μ控制器在高速轨道车辆垂向振动抑制方面具有较优的鲁棒稳定性和鲁棒性能。
)Considering the sprung mass and spring stiffness perturbed problem of the high-speed train,we apply linear fractional transformation to separate the perturbation parameter from the vertical vibration model. And weighting functions are selected to design robust μ-synthesis controller according to performance requirements,whose response is compared with the robust H∞controller based on the nominal plant model with track vertical profile irregularity as external excitation. Simulation results show that robust H∞controller performs better in suppressing vertical vibration only with external disturbance; when the model exists parameter perturbation,robust H∞controller leads to obvious deterioration,but the robust μ-Synthesis controller still performs good suppressing vibration ability. Robust μ-Synthesis controller ensures better robust stability and robust performance of closed-loop system in comparison with the robust H∞controller designed based on the nominal plant model.