基于改进型前馈控制策略的多余力抑制方法  

Surplus force suppression method based on improved feedforward control strategy

作　　者：王斌 杨练根[1] 聂磊[1] 马雷 丁鹏飞 WANG Bin;YANG Lian-gen;NIE Lei;MA Lei;DING Peng-fei(School of Mechanical Engineering,Hubei University of Technology,Wuhan 430068,China)

机构地区：[1]湖北工业大学机械工程学院,湖北武汉430068

出　　处：《机电工程》2022年第12期1686-1693,共8页Journal of Mechanical & Electrical Engineering

基　　金：国家自然科学基金面上项目(51975191)。

摘　　要：针对电液伺服系统中多余力影响加载精度的问题,提出了一种改进型前馈控制策略对多余力进行抑制。首先,分析了转向节台架试验机四轴电液加载系统中多余力产生的原因,并建立了单轴加载力与控制信号之间的数学模型;然后,考虑到位置干扰运动状态的复杂性,以及基于结构不变性原理的前馈控制中的补偿环节存在相位滞后,使用包含快速傅里叶变换(FFT)、补偿环节和双反向传播(BP)神经网络相位修正的改进型前馈控制策略对多余力进行了抑制;最后,对该控制策略进行了Simulink仿真分析和试验研究。研究结果表明:当位置干扰的频率为1 Hz、3 Hz、5 Hz时,补偿环节的相位滞后分别为1.66°、4.76°和7.92°;该策略的动态相位修正范围与有效修正范围的比值分别为0.88、0.61和0.46;随着位置干扰频率的增加,补偿环节的相位滞后增大,修正相位的相对变化范围逐渐减小,该策略对多余力的抑制效果更明显。Aiming at the problem that the surplus force affected the loading accuracy in the electro-hydraulic servo system,an improved feedforward control strategy was proposed to suppress the surplus force.Firstly,the reasons for the surplus force in the four-axis electro-hydraulic loading system of the steering knuckle bench testing machine were analyzed,and the mathematical model between the single-axis loading force and the control signal was established.Then,considering the complexity of position disturbance motion state and the compensation link's phase lagging of the feedforward control,an improved feedforward control strategy including the fast Fourier transform(FFT)of spectral sequence transformation,the compensation link and dual back propagation(BP)neural network phase correction was used to suppress the surplus force.Finally,the Simulink simulation analysis and experimental verification of the strategy were carried out.The research results show that when the frequency of position interference is 1 Hz,3 Hz,and 5 Hz,the phase lags of the compensation link are 1.66°,4.76°and 7.92°;the ratios of the dynamic phase correction range to the effective correction range are 0.88,0.61,and 0.46;with the increase of the position interference frequency,the phase lag of the compensation link increases,the relative variation range of the corrected phase gradually decreases,and the suppression effect of the method on the surplus force is more obvious.

关 键 词：电液伺服系统 加载精度 快速傅里叶变换 神经网络 相位修正算法 谱序列变换FFT算法 补偿环节 

分 类 号：TH137[机械工程—机械制造及自动化] U463.46[机械工程—车辆工程]