宽温域乘用车空气弹簧动力学建模与控制

Modeling and Control of Air Spring Dynamics in Wide Temperature Range Passenger Vehicle

目前,空气悬架在不同的车型上的装配比例越来越高,然而,整车性能的空气悬架匹配主要基于定常温下开展,很少考虑宽温域下空气悬架的控制性能。针对宽温域服役范围下乘用车的空气悬架高度控制问题,本文从空气弹簧的静态特性入手,提出了一种宽温域空气弹簧的表征模型,并模拟乘用车在非运动状态下悬架系统高度控制进行了仿真与试验,实现了车辆在宽温域下的服役性能提升。首先,通过不同温度的试验数据建立了宽温域空气弹簧模型,充分考虑了温度对橡胶以及气体的影响。其次,提出了一种基于在线线性二次调节器法(LQR)的空气悬架控制算法,该模型考虑了温度对气囊参数的影响规律。最后,在宽温域条件下验证控制器的鲁棒性。仿真与试验结果表明,考虑宽温域服役的新型控制器能实现车身高度达到目标高度并且避免出现振荡,具有良好的稳定性和鲁棒性。

At present,the assembly ratio of air suspension in different vehicle models is increasing,however,the air suspension matching of vehicle performance is mainly carried out based on the constant ambient temperature,and the control performance of air suspension in wide temperature range is rarely considered.For the problem of air suspension height control of passenger cars in wide temperature range,this paper proposes a wide temperature range air spring characterization model from the static characteristics of air springs,and simulates the height control of the suspension system of passenger cars in the non-motion state to carry out simulation and experiments,so as to realize the improvement of the service performance of the vehicle in the wide temperature range.Firstly,a wide temperature domain air spring model is established by wide temperature domain test data,which fully considers the influence of temperature on rubber and on gas.Secondly,an air suspension control algorithm based on the online linear quadratic regulator method(LQR)is proposed,which takes into account of the influence of temperature on airbag parameters.Finally,the robustness of the controller is verified under wide temperature domain conditions.Simulation and experiments show that the controller can control the body height to reach the target height and avoid oscillations under wide temperature range,with good stability and robustness.