半主动空气悬架阻尼多模型自适应控制研究

Research on Damping Multi-model Adaptive Control of Semi-active Air Suspension

针对常规自适应控制器中辨识算法的收敛速度难以跟随半主动空气悬架模型参数实际变化速度的问题,提出一种能够满足半主动空气悬架在参数大范围变化时对控制品质较高要求的阻尼多模型自适应控制方法。为改善系统控制速度,根据半主动空气悬架阻尼实际控制过程,建立了针对不同车辆运行状态的多个局部线性固定模型,同时引入一个能够重新赋初值的自适应模型,以提升系统控制精度。基于误差最小的模型切换控制策略在线选择最佳匹配模型,并采用自适应控制方法调节最佳阻尼力,从而构成系统阻尼多模型自适应控制。仿真与实车道路试验结果表明,所提出的控制方法能够有效改善半主动空气悬架在大范围行驶工况下的控制品质,车辆垂直振动加速度均方根降幅达22.8%,车辆行驶平顺性得到了明显提升。

Aiming at the problem that the convergence rate of identification algorithm in conventional adaptive controller is difficult to follow the model parameters actual change rate of semi-active air suspension, a damping multi-model adaptive control method, which could meet the high control.quality requirement of semi-active air suspension with parameters changing in wide range, was proposed. In order to improve the system control speed, multiple fixed local linear models were established according to the actual damping control process of semi-active air suspension for different vehicle operating statuses and an adaptive model which initial value could be re-assigned was introduced to enhance the system control precision. The model switching control strategy based on minimum error was used to select the best matching model online and the optimum damping force was regulated by adaptive control method, thus constituting the damping multi-model adaptive control for semi-active air suspension. Simulation and vehicle road test results showed that the proposed method could improve the control quality of semi-active air suspension in wide range driving conditions effectively and the vehicle ride comfort was improved significantly.