散粒体压制成型过程非线性负载力补偿算法研究  

Study on nonlinear load force compensation algorithm for granular materials compaction processes

作　　者：武哲 袁畅 李宝仁[1] 杨钢[1] WU Zhe;YUAN Chang;LI Baoren;YANG Gang(School of Mechanical Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]华中科技大学机械科学与工程学院,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2024年第6期63-70,共8页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国防科技基础加强计划重点基础研究项目(2021-173ZD-029)。

摘　　要：针对特殊散粒体压制成型过程发生弹塑性变形时,负载刚度呈现复杂的非线性时变特性,散粒体压制成型装置容易产生抖动现象,进而影响产品的密度均匀性和一致性问题,建立了散粒体压制成型装置电-液伺服系统的数学模型,提出了一种基于压制成型过程的非线性负载力补偿算法,通过对消补偿机制将非线性负载力对系统的影响进行抑制,使系统成为解耦线性系统.试验结果表明:当采用PID+LOC非线性负载力补偿算法时,散粒体压制成型过程中非线性负载力对控制系统性能的影响显著降低,运动控制曲线基本上呈线性变化;由于散粒体的蠕变特性,当采用比例-积分-微分(PID)控制算法时,在保压阶段容易诱发压制力的衰落振荡现象,而采用PID+LOC非线性负载力补偿算法则彻底消除了压制力的衰落振荡现象,并且提高了系统的控制精度,扩展了系统的频宽.Aiming at the problem that when the elastic-plastic deformation occurred during the special granular materials compaction process,the load stiffness presented complex nonlinear time-varying characteristics,and the granular compression molding device was prone to the jitter phenomenon,which affected the density uniformity and consistency of the product,the mathematical model of the electro-hydraulic servo system was established,and a nonlinear load force compensation algorithm was proposed based on granular materials compaction processes.The influence of the nonlinear load force on the electro-hydraulic servo system was suppressed by the cancellation compensation mechanism,so the system became a decoupled linear system.Experiment results show that when the proposed PID+LOC(proportion integration differentiation plus load observation compensator)nonlinear load force compensation algorithm is taken,the influence of nonlinear load force on the control system’s performance is significantly reduced,and the motion control curve changes linearly during granular materials compaction processes.Due to the creep characteristics of granular materials,it is easy to induce the fading oscillation phenomenon of the compacting force in the pressuremaintaining stage when taking PID as the control algorithm.However,the fading oscillation phenomenon of the compacting force is eliminated in the pressure-holding stage,and moreover the control accuracy of the system is effectively improved and the frequency bandwidth of the system is extended when the proposed PID+LOC is taken.

关 键 词：散粒体 压制成型 非线性负载 对消补偿机制 解耦线性系统 

分 类 号：TH137[机械工程—机械制造及自动化]