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针对车辆减少能量消耗与提高抗侧倾能力需求,提出了一种主/被动可切换的液压互联悬架抗侧倾控制方法.基于9自由度车辆动力学模型,考虑蓄能器、液压缸、液压泵三者之间耦合的体积-流量-压力特性,建立液压互联悬架主动控制时域模型;结合“车身侧倾角-车身侧倾角速度”相平面法及车辆侧向加速度,得到车辆侧倾稳定域,并提出液压互联悬架系统侧倾稳定性控制介入与退出判据;在此基础上,采用Backstepping非线性控制算法设计主动液压互联抗侧倾控制器.最后,分析并改进侧倾稳定性评价指标,通过在MATLAB/Simulink环境下进行高速双移线、鱼钩试验等极端工况数值仿真,验证所提出的液压互联悬架主/被动切换控制系统能在减少能量消耗的情况下能否提高车辆抗侧翻的能力.研究结果表明:所提出的控制系统能有效提高车辆抗侧翻能力;当车辆侧倾状态超出设定的侧倾稳定区域介入线时,液压互联悬架系统由被动模式切换为主动抗侧倾模式,控制车辆侧倾状态回到稳定区域,以提高车辆侧倾稳定性;当判定车辆侧倾状态满足主动控制退出条件时,液压互联悬架系统回到被动模式,以减小能量消耗.“,”In allusion to the needs for reducing energy consumption and improving anti-roll stability for vehicles,an anti-roll control method which can be switched between the passive hydraulically interconnected suspension(HIS) mode and the active HIS mode was put forward.Taking the coupling volume-flow-pressure characteristics of accumulator,cylinder and hydraulic pump into account,the time-domain control model for the HIS system was established based on a 9 degree-of-freedom (DOF) vehicle model.A roll stability region,and the HIS roll stability control criterion of intervention and exit,were proposed by combining the phase-plane method of body roll angle and the body roll rate with the lateral acceleration.Subsequently,an active antiroll controller for the HIS system was designed by the backstepping nonlinear control algorithm.Finally,an evaluating indicator of anti-roll stability was analyzed and improved,the numerical simulations including double-lane change in high speed and fishhook test in the MATLAB/Simulink environment were carried out to verify whether the anti-roll performance can be improved by the active and passive switched HIS systems with lower energy consumption.The results show that the proposed control system can improve the anti-roll performance of vehicles.If the vehicle roll states are beyond the roll stability region,the HIS system will switch from the passive mode to the active mode to control vehicle roll states back to the stability region,with the purpose of improving roll stability of vehicles.Besides,the HIS system will switch back to the passive mode when satisfying the exit condition so as to reduce the energy consumption.