基于新型跟踪微分器的车轮滑移率跟踪控制

Tracking control of wheel slip based on new tracking differentiator

针对汽车直接横摆力矩控制系统和自动紧急制动系统对快速、准确和稳定的车轮滑移率跟踪控制的需求,提出了一种基于新型跟踪微分器的车轮滑移率跟踪控制器.首先,分别以车轮制动力矩导数、车轮滑移率跟踪误差及其导数作为控制量和状态量,建立了包含复合加性不确定性的车轮滑移率跟踪控制模型.随后,设计了一种新型跟踪微分器来估计车轮滑移率跟踪误差及其导数,为实现车轮滑移率全状态反馈跟踪控制奠定基础.以新型跟踪微分器输出为基础,利用模糊推理系统在线估计和补偿模型的复合加性不确定性,并结合幂函数和线性函数设计了一种具有快收敛速度特征和抑制颤振能力的车轮滑移率跟踪控制律.最后,从实际应用角度仿真验证所提出的车轮滑移率跟踪控制器的可行性和有效性.结果表明,所提出的车轮滑移率跟踪控制器可以快速、准确和稳定地跟踪任意车轮目标滑移率,并且车轮滑移率跟踪残差不大于0.333%.

Aiming at the requirements of direct yaw moment control system and automatic emergency braking system for the fast,accurate and stable tracking control of wheel slip,a wheel slip tracking controller based on a new tracking differentiator was proposed.First,a tracking control model for the wheel slip with lumped additive uncertainty was established by using the derivative of the wheel braking moment as a control variable and using the tracking error of the wheel slip and its derivative as state variables.Then,a new tracking differentiator was designed to estimate the tracking error of the wheel slip and its derivative to lay a foundation for full-state feedback(FSFB)tracking control of the wheel slip.Based on the output of the new tracking differentiator,a fuzzy inference system was used to estimate and compensate the lumped additive uncertainty,and a tracking control law for the wheel slip with the characteristic of fast convergence speed and the flutter-suppression ability was designed by combining the power function with the linear function.Finally,the feasibility and the effectiveness of the proposed controller were verified by simulation from the practical application.The simulation results show that the controller can track any desired wheel slip quickly,accurately and stably,and the wheel slip tracking residual is not greater than 0.333%.