玉米联合收获机清选控制系统设计与试验

Design and experiment of cleaning control system for corn combined harvester

玉米联合收获机清选系统工况复杂,存在收获质量差、效率不高等问题。基于此,设计一套清选损失率控制为主同时兼顾含杂率的自动控制系统。首先分析以风机转速、振动筛转速和喂入量为影响因素,损失率、含杂率为评价指标的正交试验数据,获取影响损失率和含杂率的主次因素,提出清选系统自动控制策略;其次,为开展控制策略和算法的研究,建立清选系统中的风机转速、振动筛转速调节装置以及收获机纵向运动的数学模型,设计离散化PID控制算法。最后,基于MATLAB/dSPACE软硬件环境,搭建清选控制系统的硬件在环仿真平台,并进行控制器在环测试。试验证明:本文设定的双目标联合控制策略和控制算法,能够有效降低清选损失率、含杂率,其中清选损失率降到2.7%左右,含杂率为2.8%左右。

The cleaning system of maize combined harvester is complicated and has the problems of poor harvest quality and low efficiency.Based on this,a set of automatic control system was designed,which mainly controlled the cleaning loss rate and simultaneously controlled the impurity content rate.Firstly,based on the orthogonal test data of fan speed,shaker speed and feeding amount as the influencing factors,loss rate and impurity content rate as the indicators,the primary and secondary factors affecting loss rate and impurity content rate were obtained,and the automatic control strategy of cleaning system was proposed.Secondly,in order to carry out the research of control strategy and algorithm,the mathematical models of the fan speed,the shaker speed regulating device and the longitudinal movement of the harvester in the cleaning system were established,and the discrete PID control algorithm was designed.Finally,based on the software and hardware environment of MATLAB/dSPACE,the hardware-in-the-loop simulation platform of the cleaning control system was built,and the controller in the loop test was carried out.The experimental results show that the dual-objective joint control strategy and control algorithm set in this paper can effectively reduce the cleaning loss rate and impurity content rate to the target range,in which the cleaning loss rate is about 2.7%and the impurity content rate is about 2.8%.