摘要
为充分利用四轮独立驱动(4WID)电动轮汽车各轮驱动电机转矩独立可控及调节迅速的特点,对其横向稳定性控制问题进行研究。以车辆动力学理论为基础,基于动态仿真平台Matlab/Simulink建立包含"魔术公式"轮胎模型以及电机控制模型在内的九自由度整车闭环动力学系统。利用分层思想,上层运用模糊控制理论,分别设计以车身横摆角速度和质心侧偏角为控制变量的模糊控制器,并采用"当质心侧偏角较小时以理想横摆角速度跟踪控制为主,当质心侧偏角较大时以抑制质心侧偏角过大为主"的耦合协调控制策略产生所需附加主动横摆力矩。根据附加横摆力矩的大小,在下层分配设定一个阈值判断模块,通过判定选取效率车轮"差值驱动"及"差值驱动+差动制动相结合"的四轮驱动/制动协同分配模式来产生附加横摆力矩的方法对汽车失稳状态进行主动干预,最后在汽车典型的试验工况下进行稳定性控制的仿真测试。结果表明:采用的控制系统能够将质心侧偏角控制在稳定范围内,并能够很好地跟踪汽车的期望横摆角速度,提高电动轮汽车极限行驶工况下的横向稳定性。
This paper involves the study of the lateral stability control of 4WID electric-wheel vehicle to fully employ the independent controllability and rapid adjustment of each wheel＇s driving motor torque. A nine-DOF dynamic closed-up vehicle system, including a ＂magic formula＂tire model and a motor control model,was established with the theory of vehicle system dynamics and the simulation software Matlab/Simulink applied. Based on the layered method and the fuzzy control theory,the upper layer was designed with fuzzy controllers that used body yaw rate and the sideslip angle as controlled variable. The desired additional active yaw moment was produced by using the coupling and coordinated control strategy that when the sideslip angle is small,the focus is chiefly on the tracking control of the desired yaw rate; when it is large,the focus is mainly on the suppression of excessive sideslip angle. According to the desired additional yaw moment,a threshold determination module was set in the lower distribution control layer,by which the mode that an efficiency wheel combined with＂differential drive＂or ＂differential drive and differential brake＂ wheel drive/brake force distribution was determined and selected to generate additional yaw moment to intervene actively with vehicle instability. Finally, the simulation test of stability control was conducted under typical vehicle test conditions. The results show that the control system can confine the sideslip angle within a stability range, and at the same time can efficiently track the desired vehicle yaw rate so as to improve the lateral stability of electric-wheel vehicle in extreme driving conditions.
出处
《中国测试》
CAS
北大核心
2016年第6期104-111,共8页
China Measurement & Test
基金
教育部春晖计划资助项目(Z2013024)
四川省新能源汽车电控技术创新支撑项目(15203559)
四川省科技厅重点资助项目(2011J00043)
西华大学研究生创新基金项目(ycjj2015034)
