包含磁力齿轮的位置伺服系统的极点配置与积分校正控制

Control strategy of servo positioning system with magnetic gears based on pole assignment and integral compensation

为克服磁力齿轮的低刚度特性,提高伺服系统动态性能和抗干扰能力,采用以输出位置作为状态反馈构成全闭环控制系统的策略。建立既考虑磁力齿轮的动力学特性,又考虑摩擦负载和外界负载的综合动力学模型,进而得到系统的频域表达和状态空间表达。利用极点配置法,合理选择闭环系统主导极点,并设定状态反馈系数向量,以获得预想的系统性能。为进一步增强系统的抵抗负载波动能力,引入积分校正环节对位置误差信号进行积分运算,构建基于积分校正方法的控制系统。对所建立的2类控制系统进行数值仿真。研究结果表明:2种控制方法均能使直线滑台快速而准确地到达指令位置,实现对输入信号的良好跟踪。但含积分校正器控制系统具有更好的抗干扰能力和定位精度,更适用于具有大波动负载和外界干扰的场合。

The magnetic gears have the characteristics of low stiffness, which is normally regarded as the main barrier for their widespread application in the systems with high-bandwidth dynamic transients. A closed loop control strategy for the linear positioning system with magnetic gears was proposed. A comprehensive dynamic mathematical model, which takes into account the dynamic of magnetic gears, as well as the frictional load and external force, was proposed. Based on the dynamic model, a frequency-domain expression and a state-space expression were both obtained. For realizing the desired dynamic response, a pole placement algorithm was used. An extra integral regulation was introduced to strengthen the ability of rejecting the load disturbances. The results show that those two types of controllers can adjust the position of the linear stage accurately and fast. The second controller with integral regulation has a higher anti-disturbance ability and positioning accuracy.