基于时变扰动抑制的动力换挡拖拉机起步控制方法

针对拖拉机起步工况复杂,起步控制系统存在建模不确定性、参数摄动和时变扰动等问题,为提高动力换挡拖拉机起步品质和驾驶员操作舒适性,提出了基于时变扰动抑制的拖拉机起步控制方法.首先,以动力换挡变速箱(Power shift transmission,PST)为研究对象,通过分析拖拉机起步过程的动态特性建立PST起步动力学模...

Starting Control Method for Power Shift Tractor Employing Time-varying Disturbance Rejection

Due to the complex starting conditions of the power shift tractor,there are many problems such as modeling uncertainty,parameter perturbation and time-varying disturbance in the system.Therefore,a novel starting control method employing the time-varying disturbance rejection was proposed to improve the starting performance of the power shift tractor and the drivers’operating comfort.Firstly,the power shift transmission(PST)starting dynamic model was established by analyzing the dynamic characteristics of the starting process.Using the starting jerk and slipping friction work as the evaluation indicators to construct the performance function of the controller.Then a high-order disturbance observer(HDO)was introduced to estimate the time-varying disturbance and its derivatives in the starting process.The linear quadratic regulator(LQR)was used to obtain the optimal starting control law.The results of numerical calculation showed that HDO could effectively estimate the time-varying disturbance,and it could effectively suppress the influence of the disturbance and improve the robustness of the system combining with LQR.Finally,a co-simulation model of high-power tractor driveline was built based on Matlab/Simulink and AMESim,and proportional integral observer(PIO)was introduced as the comparison to verify the effectiveness of the starting control strategy.Taking 60%throttle as the example,the results showed that the maximum starting jerk by HDO were 12.25 m/s³and 11.32 m/s³in transportation and ploughing conditions,respectively,which were 21.92%and 22.20%lower than that by LQR,respectively.Besides,the slipping friction work by HDO were 0.49 kJ and 0.11 kJ lower than that by LQR in transportation and ploughing conditions,respectively.In different starting intentions and working conditions,the proposed method could effectively reduce the starting jerk and friction work of the power shifting tractor during the starting process,and had better starting quality and control robustness.