摘要
大吨位液压机主缸在不同运动阶段通常需要不同速度以兼顾压制效率和制品性能,但由于其属于大惯量系统,常规控制方式难以同时满足运动过程的快速性、精确性与平稳性,该文通过改进控制方式以提高此三个特性。首先,分析主缸运动系统的工作原理,建立其数学模型和控制方程;其次,利用AMESim搭建液压系统仿真模型,并通过Simulink创建AMESim仿真模型的控制模块,从而组成闭环控制联合仿真平台,然后通过试验数据验证了仿真模型的准确性。仿真结果显示,采用二次轨迹跟踪指令、变增益以及积分分离相结合的PI控制算法的控制方式比传统的采用阶跃式指令的开环高低速切换控制方法在高低速切换过程的平稳性、速度控制的精确性、压力冲击以及制品的压制效率等性能方面都有较大的提升,其消除了速度突变、下降时间缩短31%、压力冲击减小51.6%,负载干扰下精度提高64%。
To ensure suppression efficiency and product performance, it is necessary to set different velocity during large-tonnage hydraulic press main-cylinder moving in different phase. Because of its large inertia, normal control mode is difficult to be simultaneously satisfied all the rapidity, accurately and stationarity of the main-cylinder＇ s movement process. To improve the three features, the control mode is modi- fied. Firstly analyzing the operating principle of main-cylinder moving system and establishing its mathematical model. Then using AMES- im to establish the simulation model of hydraulic system and using Simulink to create the controlling module of AMESim model that makes up the co-simulation platform. The trial data verifies the simulation model that has high reliability. The simulation result shows, comprised to the control effects of the traditional method that uses the step instructions and is of open-loop high-low switching, PI controlling algo- rithm that combines quadrics trajectory tracking, variable gain and integral separation method can improve the stationarity of velocity switching, the accuracy of the steady stage velocity and suppression efficiency, also can reduce the pressure surge. By using the above meth- od, the velocity mutation is eliminated, the fall time is reduced by 31%, the pressure shock is decreased by 51.6% and the velocity accuracy is improved by 64% in the presence of load disturbance.
出处
《液压气动与密封》
2015年第2期48-54,共7页
Hydraulics Pneumatics & Seals
基金
福建省科技重大专项(2011HZ006-1)
福建省科技创新平台建设项目(2011H2008)
关键词
液压机
电液控制
速度闭环
联合仿真
hydraulic press
electro-hydraulic control
velocity closed-loop
co-simulation
