摩擦对电动直线负载模拟器的影响及其抑制研究

为抑制摩擦非线性因素对电动直线负载模拟器（ELLS）的影响，采用仿真与实验结合的方法分析摩擦对ELLS的影响。利用遗传算法对系统中的摩擦模型进行辨识，并得出了系统摩擦力与速度的关系；提出了一种摩擦前馈加变增益PID的混合控制方法，摩擦前馈用于消除摩擦对系统的影响，变增益PID用于进一步抑制系统在低速时的相位滞后；进行了对比仿真与实验。仿真分析与实验结果表明：与传统PID控制相比，采用摩擦前馈加变增益PID控制的ELLS加载波形畸变被抑制、加载误差与相位滞后均明显减少；所提出控制方法能够较好地抑制摩擦对ELLS的影响，提高加载精度。

Effect of Friction on Electric Linear Load Simulator and Research on Friction Suppression

In order to suppress the effect of friction on electric linear load simulator (ELLS), the simulation analysis and experimental methods are used to analyze the effect of friction on ELLS, the genetic algorithm is used to identify the friction model in ELLS, and the relationship between friction and velocity is obtained. A hybrid control method of friction feedforward and variable gain PID is proposed, the friction feedforward compensation is used to eliminate the effect of friction, and the variable gain PID is used to further suppress the phase lag of ELLS at low velocity. Comparative simulation and experiment were made. The simulated analysis and the experimental results show that, compared with traditional PID control, the loading wave distortion of ELLS using the friction feedforward and variable gain PID is suppressed, and the loading error and phase lag are significantly reduced. The proposed control method can better suppress the effect of friction on ELLS and improve the loading accuracy.