液压集成式互联馈能悬架系统的机理及半主动控制研究

To alleviate energy consumption problems of heavy trucks and also improve the driving safety, energy-harvesting suspension technology and interconnected suspension technology have attracted considerable attention. Integrating the structural characteristics of the energy harvesting suspension and the hydraulic interconnected suspension, as well as the performance characteristics of the inerter-spring-damping (ISD) suspension, a novel hydraulic integrated interconnected suspension based on the hydraulic energy-harvesting shock absorbers (HESA-HIS) is proposed. Its vibration isolation mechanism and the coupling effect between the electric damping and the stiffness are explored. Firstly, the system impedance transfer matrix is derived based on the mechanical-electric-fluid similarity theory, and the corresponding frequency-domain vehicle model is established to explore the vibration isolation mechanism. Then, the time-domain nonlinear HESA-HIS output force is modeled under various operating conditions based on the regression support vector machine, taking into account the coupling effect between the hydraulic motor and the accumulator and also the pressure drop of each hydraulic component. The vehicle dynamics model is then established, to analyze the coupling effect between the generator load and the suspension stiffness. Key parameters are also optimized based on the time-domain nonlinear model. Finally, to deal with the control problem of this nonlinear fast time-varying system, two linear vehicle models are established, characterizing the piecewise linear feature of the HESA-HIS. The dual-mode adaptive control method is proposed to design the semi-active control law of the generator load, with the purpose to achieve the optimal vehicle dynamics performance. The research results will provide a theoretical and technical basis for improving the fuel economy, handling stability and ride comfort of heavy-duty trucks.

为改善重型货车能耗大、行车安全性差的问题，馈能悬架与液压互联悬架引起了广泛关注。结合馈能、互联两种悬架的结构特点与惯容-弹簧-阻尼（ISD）悬架的性能特点，本研究提出一种液压集成式互联馈能悬架系统（HESA-HIS），探明它的隔振机理及馈能系统电阻尼-刚度耦合机理。首先，基于机-电-液相似性理论推导系统阻抗传递矩阵，建立相应车辆频域模型，探究隔振机理。然后，基于回归型支持向量机建立HESA-HIS系统多工况下的非线性模型，计及系统部件之间耦合效应和各液压元件压降规律，进而建立整车动力学模型，研究电机负载-悬架刚度耦合机理并优化参数。最后，针对该非线性快时变系统，建立可表征HESA-HIS分段线性特征的两种线性车辆模型，提出双模式自适应控制方法设计电机负载半主动控制律，以达到车辆最佳动力学性能。研究结果将为改善重型货车燃油经济性、操纵稳定性与乘坐舒适性提供理论与技术基础。

液压互联馈能悬架在重型商用车车体控制与节能减排方面具有独特优点。本项目以提升液压集成式互联馈能悬架（HESA-HIS）的动力学性能与能量回收功率为研究目标，对其频域建模与时域建模、振动传递特性、参数灵敏度分析与优化以及半主动控制等展开了理论和试验研究。基于液压阻抗和传递矩阵法建立了HESA-HIS的频域模型，结合4自由度半车模型研究了互联馈能悬架的振动传递特性。搭建了液压集成式互联馈能悬架样机，进行了样机台架试验和单个元件的特性试验，结合试验结果与理论推导，建立了可准确预测各种激励和负载下减振器输出力的HESA-HIS时域模型。基于时域模型和整车14自由度模型，以提高乘坐舒适性、转向行驶时的操纵稳定性和能量回收功率为目的，对液压集成式互联馈能悬架系统的参数进行了灵敏度分析和参数优化。为进一步提高车辆低频激励下的稳定性和高频激励下的乘坐舒适性，针对HESA-HIS提出了可全工况改善动力学性能的分层半主动控制算法，其显著降低了低频工况下车身最大姿态速度、提高了姿态回稳速度，降低了高频工况下车身加速度均方根值，对操纵稳定性与乘坐舒适性均有明显提高。研究成果对液压互联馈能悬架的推广应用、提高重型商用车的舒适性、操纵稳定性与燃油经济性具有重要意义。