为改善载货车辆极限状态的操纵稳定性和侧翻稳定性,在非线性工作域内进行主动横摆和侧倾力矩的改进型滑模控制,实现载货车辆横摆-侧倾运动的联合控制。利用扇形域建立非线性悬架和轮胎的T-S模型,结合模糊观测器获取悬架和轮胎动态模型...为改善载货车辆极限状态的操纵稳定性和侧翻稳定性,在非线性工作域内进行主动横摆和侧倾力矩的改进型滑模控制,实现载货车辆横摆-侧倾运动的联合控制。利用扇形域建立非线性悬架和轮胎的T-S模型,结合模糊观测器获取悬架和轮胎动态模型参数。基于T-S方法的横摆-侧倾联合控制模型,考虑横向载荷偏移对期望横摆角速度的影响,建立横摆状态和侧倾状态滑模面,设计了改进型滑模方法的动态滑模参数,并对控制系统进行Lyapunov稳定性分析。在Trucksim中采用Sine with Dwell转向输入进行验证,结果表明:结合模糊观测器的T-S方法能够准确模拟模型参数的非线性变化,动态滑模参数具有不同路面摩擦状态的自适应性,结合T-S模型的动态参数滑模方法能显著提高载货车辆极限状态下的稳定性,控制性能优于传统滑模方法。展开更多
采用转矩环取代传统的电流环,可减小非理想反电势无刷直流电机(brushless DC motor,BLDCM)的转矩脉动,提高其控制性能,而转矩环中反馈转矩计算的关键在于绕组反电势的准确获取。建立考虑参数偏差的滑模观测器(sliding-mode observer,SMO...采用转矩环取代传统的电流环,可减小非理想反电势无刷直流电机(brushless DC motor,BLDCM)的转矩脉动,提高其控制性能,而转矩环中反馈转矩计算的关键在于绕组反电势的准确获取。建立考虑参数偏差的滑模观测器(sliding-mode observer,SMO)对反电势进行实时观测,定量分析了定子电阻偏差对观测结果的影响,分析表明反电势观测的稳态误差等于电阻偏差量与电流的乘积。为消除这一影响,利用李雅普诺夫(Lyapunov)稳定性理论,设计了定子电阻参数辨识的自适应率,在线辨识得到的电阻参数用于调整SMO的系数矩阵,构成了新型的自适应滑模观测器。最后,利用RT-LAB实时控制器进行实验,验证了上述分析结果的正确性,证明了所提方法能够正确快速地观测无刷直流电机反电势。展开更多
Inspired by the idea that bionic non-smooth surfaces(BNSS) can reduce fluid adhesion and resistance, and the effect of bionic V-riblet non-smooth structure arranged in tire tread pattern grooves surface on anti-hydrop...Inspired by the idea that bionic non-smooth surfaces(BNSS) can reduce fluid adhesion and resistance, and the effect of bionic V-riblet non-smooth structure arranged in tire tread pattern grooves surface on anti-hydroplaning performance was investigated by using computational fluid dynamics(CFD). The physical model of the object(model of V-riblet surface distribution, hydroplaning model) and SST k-ω turbulence model were established for numerical analysis of tire hydroplaning. With the help of a orthogonal table L16(45), the parameters of V-riblet structure design compared to the smooth structure were analyzed, and obtained the priority level of the experimental factors as well as the best combination within the scope of the experiment. The simulation results show that V-riblet structure can reduce water flow resistance by disturbing the eddy movement in boundary layers. Then, the preferred type of V-riblet non-smooth structure was arranged on the bottom of tire grooves for hydroplaning performance analysis. The results show that bionic V-riblet non-smooth structure can effectively increase hydroplaning velocity and improve tire anti-hydroplaning performance. Bionic design of tire tread pattern grooves is a good way to promote anti-hydroplaning performance without increasing additional groove space, so that tire grip performance and roll noise are avoided due to grooves space enlargement.展开更多
文摘为改善载货车辆极限状态的操纵稳定性和侧翻稳定性,在非线性工作域内进行主动横摆和侧倾力矩的改进型滑模控制,实现载货车辆横摆-侧倾运动的联合控制。利用扇形域建立非线性悬架和轮胎的T-S模型,结合模糊观测器获取悬架和轮胎动态模型参数。基于T-S方法的横摆-侧倾联合控制模型,考虑横向载荷偏移对期望横摆角速度的影响,建立横摆状态和侧倾状态滑模面,设计了改进型滑模方法的动态滑模参数,并对控制系统进行Lyapunov稳定性分析。在Trucksim中采用Sine with Dwell转向输入进行验证,结果表明:结合模糊观测器的T-S方法能够准确模拟模型参数的非线性变化,动态滑模参数具有不同路面摩擦状态的自适应性,结合T-S模型的动态参数滑模方法能显著提高载货车辆极限状态下的稳定性,控制性能优于传统滑模方法。
文摘采用转矩环取代传统的电流环,可减小非理想反电势无刷直流电机(brushless DC motor,BLDCM)的转矩脉动,提高其控制性能,而转矩环中反馈转矩计算的关键在于绕组反电势的准确获取。建立考虑参数偏差的滑模观测器(sliding-mode observer,SMO)对反电势进行实时观测,定量分析了定子电阻偏差对观测结果的影响,分析表明反电势观测的稳态误差等于电阻偏差量与电流的乘积。为消除这一影响,利用李雅普诺夫(Lyapunov)稳定性理论,设计了定子电阻参数辨识的自适应率,在线辨识得到的电阻参数用于调整SMO的系数矩阵,构成了新型的自适应滑模观测器。最后,利用RT-LAB实时控制器进行实验,验证了上述分析结果的正确性,证明了所提方法能够正确快速地观测无刷直流电机反电势。
基金Project(51405201)supported by the National Natural Science Foundation of ChinaProject(1291120046)supported by the Jiangsu University Advanced Talents Initial Funding,China+1 种基金Project(QC201303)supported by the Open Fund of Automotive Engineering Key Laboratory,ChinaProject(2014M551509)supported by the China Postdoctoral Science Foundation
文摘Inspired by the idea that bionic non-smooth surfaces(BNSS) can reduce fluid adhesion and resistance, and the effect of bionic V-riblet non-smooth structure arranged in tire tread pattern grooves surface on anti-hydroplaning performance was investigated by using computational fluid dynamics(CFD). The physical model of the object(model of V-riblet surface distribution, hydroplaning model) and SST k-ω turbulence model were established for numerical analysis of tire hydroplaning. With the help of a orthogonal table L16(45), the parameters of V-riblet structure design compared to the smooth structure were analyzed, and obtained the priority level of the experimental factors as well as the best combination within the scope of the experiment. The simulation results show that V-riblet structure can reduce water flow resistance by disturbing the eddy movement in boundary layers. Then, the preferred type of V-riblet non-smooth structure was arranged on the bottom of tire grooves for hydroplaning performance analysis. The results show that bionic V-riblet non-smooth structure can effectively increase hydroplaning velocity and improve tire anti-hydroplaning performance. Bionic design of tire tread pattern grooves is a good way to promote anti-hydroplaning performance without increasing additional groove space, so that tire grip performance and roll noise are avoided due to grooves space enlargement.
