提高直接驱动电动机系统刚度的机电一体化设计

MECHATRONICS DESIGN OF STIFFNESS ENHANCEMENT OF DIRECT-DRIVE MOTOR SYSTEMS USING ER VARIABLE DAMPER

直接驱动电动机具有结构简单、控制性能高的特点 ,但扰动转矩直接影响其控制性能 ,较高的伺服刚度是减小转矩扰动对控制精度影响的有效手段。然而 ,过高的刚度会使被控直接驱动电动机系统不稳定 ,甚至产生振荡。设计一种电流变可调阻尼器 ,直接附加在电动机的转轴上 ,通过外加电压可以调节电流变阻尼器的阻尼系数 ,从而可以提高系统的刚度而又不会引起系统的振荡。推导了电流变可调阻尼器的阻尼系数模型 ,并通过位置式PD控制直接驱动电动机系统的数值仿真 ,验证了上述基于电流变可调阻尼器的直接驱动电动机系统刚度提高设计方法的有效性。

Direct-drive (DD) motors have the characteristics of simple structure and high controllability without reduction gears However,DD motors are more sensitive to the disturbance and parameter variation than other motors which have reduction gears Enhancement of the stiffness of DD motors is one of effective methods to reduce these influence on the accuracy of the systems,but very high stiffness will lead to unstable,even become vibratory Viewed from mechatronics design,a variable-viscous electrorheological (ER) fluid damper whose viscous coefficient depends upon the applicable voltage is designed,and directly attached on the shaft of DD motor to achieve high servo stiffness control The structure of the variable-viscous ER damper is presented,and the viscous coefficient model of the designed damper is developed The validation of this mechatronics design is demonstrated with a simulation of the position PD control DD motor system