机电作动器舵回路系统动态特性分析

Analyzing Dynamic Characteristics of Rudder Loop System for an Electro-mechanical Actuator

为了提高机电作动器舵回路系统动态特性,以基于行星滚柱丝杠副的机电作动器舵回路系统为研究对象,建立一种采用一维伺服控制系统模型与三维机构动力学模型相结合的闭环耦合模型。通过变量信息实时交互实现联合仿真,进一步探究机电作动器中行星滚柱丝杠副摩擦力矩、刚度和间隙等非线性因素对舵回路系统的动态特性影响。结果表明:摩擦力矩是影响系统响应稳态值的主要因素;当系统输入阶跃信号时,刚度和间隙是造成系统振荡的主要原因;考虑摩擦力矩时,系统的跟踪精度降低,响应速度变慢;提高刚度可避免系统大幅振荡,能够保证系统稳定性;减小间隙量,可降低系统阶跃响应波动幅值,并加快系统调节时间。

In order to enhance the dynamic characteristics of the rudder loop system of an electro-mechanicalactuator with the planetary roller screw mechanism, this paper develops a closed-loop coupling model that combinesthe one-dimensional servo control model with the three-dimensional dynamic model. Comprehensive simulations areperformed with the real-time interaction of information on variables, and the influence of nonlinear factors of aplanetary roller screw such as frictional moment, stiffness and clearance on the dynamic characteristics of the rudderloop system is analyzed. The results indicate that the frictional moment is the mMn factor that influences the steady-state value of the system＇s step response. Stiffness and clearance can cause the oscillation of the system when itsstep signal is input signal, and the tracking precision and response speed of the system decreases when the frictionalmoment is taken into account. Furthermore, increasing stiffness can avoid the oscillation of the system, thusimproving its stability. The fluctuation amplitude of the step response can be decreased and the time for regulatingthe system can also he increased by decreasing the clearance of the planetary roller screw.