一种联合收获机脱粒滚筒转速的鲁棒预测控制

Robust Predictive Palstance Control of Combine Cylinder Threshing

联合收获机的轴流式脱粒滚筒转速系统具有强非线性、不确定、滞后、大干扰等特点,以收获机的行走速度和喂入量为控制量,滚筒转速为被控量,建立闭环控制系统,设计时变的鲁棒稳定控制器。在频域内基于比例微分校正技术补偿无级变速传动的滞后环节影响;基于近似模型预测的连续预测控制律保证了大范围工作的控制系统性能;同时,设计收敛的非线性干扰观测器,对复杂环境联合收获机的时变干扰进行在线估计,进行前馈补偿提高系统的鲁棒性。最后,通过仿真和试验验证了所提方法的有效性。

To the problem that the threshing cylinder palstance control system of the combine has strong nonlinearity,uncertainty,time-delay,and complex disturbance,a closed control system is modeled with the walking speed and the feeding volume as the control inputs,and cylinder palstance as the controlled quantity.A robust time-varying controller is proposed.Derivative correct technology is used to compensate the phase time-delay of the variable-speed drive in frequency domain,and the predictive control input is designed on the basis of approximate linear predictive model and receding horizon optimal to guarantee the system stability in a large work range.A nonlinear disturbance observer is applied to estimate the time-varying disturbance online for the combine within the complex environment.The feed-forward compensation improves the system robustness.The simulation experiment show the validity of the proposed method.