基于最小能耗的电动汽车横摆稳定性灰色预测可拓控制研究

Study on the Grey Predictive Extension Control of Yaw Stability of ElectricVehicle Based on the Minimum Energy Consumption

根据四轮驱动轮毂电机电动汽车车轮驱动转矩独立可控的特点,通过控制轮毂电机的输出转矩从而控制四个车轮的驱动力/制动力,产生附加横摆力矩,实现电动汽车的横摆稳定性控制。整车控制策略采用分层控制,上层为附加横摆力矩控制器,分别设计基于横摆角速度的模糊控制器、基于质心侧偏角的模糊控制器和可拓联合控制器,下层为驱动力分配控制器,分为稳定性控制模式、最小能耗控制模式和联合控制模式,采用伪逆优化算法对各车轮的驱动力矩进行优化分配。采用灰色控制模型对实际的横摆角速度和质心侧偏角数据进行预处理。根据电动汽车行驶状态,将控制域划分为经典域、可拓域和非域,在不同的域内采用不同的控制模式,在保证整车横摆稳定性的同时降低整车驱动能耗,提高续航里程。在Matlab/Simulink软件中建立整车动力学模型,并在双移线工况下进行横摆稳定性控制与最小能耗控制的仿真分析。仿真结果表明,整车控制策略能有效保障汽车行驶时的横摆稳定性,同时可以降低整车的驱动能耗。最后,利用轮毂电机试验台并采用Carsim和LabVIEW进行硬件在环试验,验证整车控制策略。

According to the characteristics that the driving torque of each wheel of a four-wheel hub motor drive electric vehicle can beindependently controlled,the stability control of the electric vehicle could be realized by controlling the output torque of wheel hub motor(i.e.,adjusting the wheel driving force or brake force)to generate additional yaw moment.The hierarchical control strategy is applied forthe vehicle stability control.The upper layer is a yaw moment controller,which includes two fuzzy controllers based on yaw rate andsideslip angle,respectively,and an extension combination controller.The lower layer is a driving force distribution controller,whichutilizes the pseudo inverse algorithm to optimize the driving torque allocation of each wheel.Its control modes are divided into stabilitycontrol,minimum energy consumption control and combination control.The gray control model is used to preprocess the actual yaw rateand sideslip angle.According to the electric vehicle driving state,the control domain is divided into three domains,i.e.,classic domain,extension domain and non-domain.And in different domains,different control modes are employed to ensure the vehicle’s stability andreduce the energy consumption.The vehicle dynamics model is established in Matlab/Simulink.The simulations of stability control andminimum energy consumption control have been carried out in double lane change condition.The simulation results show that theproposed control strategy can effectively guarantee the vehicle’s stability and minimize the energy consumption.Finally,the controlstrategy was verified on a wheel hub motor test bench based on Carsim and LabVIEW.