轮毂电机驱动车辆多维度动力学耦合机理及解耦控制研究

As one important development direction of next-generation electric vehicle, In-wheel Motor Drive Vehicle (IWMDV) has significant potential to improve vehicle performance. While, due to the heavy unsprung mass and the redundant actuated electric wheels with constraints, the dynamic coupling problems of IWMDV are extreme complex, which have brought new opportunities and challenges for vehicle dynamics control. For elucidating the multi-dimensional dynamic coupling mechanisms on IWMDV, a nonlinear vehicle dynamic model with multi-degrees of freedom will be established to research the coupling properties of motion states, tire forces, and vertical vibration transmission. And then, a vibration reduction system inside the electric wheel will be designed, and the synthesizing optimization approach for vibration reduction system and vehicle suspension is to be proposed to reduce the vibration negative influences. Meanwhile, the problems on motion states coupling and electric wheel torque distribution are to be solved based on modern control theory, where, the coupled motion states will be decoupling controlled by vehicle states estimation and resultant forces reintegration. And then, according to the dynamic performance requirements in various conditions, the electric wheel torque distribution equations with adaptively adjustable weighting coefficient will be established. The intelligence-optimized algorithm is to be used to solve the equations, based on that, vehicle decoupling control will be achieved by the effective distribution of the torque from in-wheel motor and braking system. The vehicle stability and ride comfort will be realized.

轮毂电机驱动车辆作为下一代电动汽车的重要发展方向之一，在提升车辆性能潜力的同时，其较大的簧下质量以及过驱动、有约束、静不定的电动轮系统使车辆动力学耦合问题更加复杂，给车辆动力学控制带来了新的机遇和挑战。本申请拟通过车辆动力学系统建模，分析车辆运动状态、轮胎力的耦合特性及垂向激励的传递特性，以阐明车辆多维度动力学耦合机理；研究电动轮内减振系统设计及其与主悬架系统的综合优化方法，实现电动轮垂向负效应的有效抑制；同时，针对车辆运动状态耦合及电动轮转矩分配问题，拟基于现代控制理论，通过车辆多状态信息估算、车辆合力及合力矩重构进行运动状态解耦控制，然后，根据不同工况下车辆动力学性能需求，构建权重系数自调节的电动轮转矩控制分配方程，基于优化算法求解电动轮转矩的最优分配，最后通过轮毂电机及制动器的输出转矩实现车辆动力学解耦控制。最终提高车辆行驶稳定性和平顺性。

轮毂电机驱动车辆作为下一代电动汽车的重要发展方向之一，在提升车辆性能潜力的同时，其较大的簧下质量以及过驱动、有约束、静不定的电动轮系统使车辆动力学耦合问题更加复杂，给车辆动力学控制带来了新的机遇和挑战。本项目建立了能较全面和准确反应轮毂电机驱动车辆多维度动力学特性的非线性多自由度“人-车-路”系统动力学模型；设计了基于轮内减振系统的电动轮优化结构，提出了一种轮内减振系统和车辆悬架系统综合控制的减振方法，试制了一套带轮内减振系统的“电动轮/悬架”系统，并通过台架实验，验证了减振系统的有效性，提高了轮毂电机驱动车辆的行驶平顺性和电机工作可靠性；针对轮毂电机驱动车辆多维度动力学耦合的问题，设计了分层控制架构，采用非线性滑模控制实现了车辆纵向、横向、横摆运动的解耦控制，提高了车辆操纵稳定性；针对电动轮系统冗余驱动的问题，采用多目标优化方法，以车辆操纵稳定性和驱动系统经济性为优化目标，实现了多轮毂电机的转矩优化分配，提高了车辆行驶安全性和经济性。基于本项目所研究的车辆动力学控制，课题组针对智能汽车自适应巡航中的动力学控制开展了研究，将轮毂电机驱动车辆作为智能汽车平台，扩展了轮毂电机驱动车辆的应用领域，也为智能汽车动力学控制提供了参考。