主动电磁轴承-刚性转子系统加速响应的鲁棒性

Acceleration Responses Robustness of Active Magnetic Bearings-Rigid Rotor System

加速响应是主动电磁轴承-刚性转子系统中一个重要的动力学特性,目前对支承在主动电磁轴承上的转子系统动力特性的研究主要以稳态特性为主,而对加速特性的研究较少。该文以主动电磁轴承-刚性转子系统为对象,分别研究PID控制和H∞鲁棒控制时转子系统的加速特性。首先,建立主动电磁轴承-刚性转子系统在加速运动过程中的动力学方程。然后,分析加速运行过程中PID控制器和H∞鲁棒控制器的设计原则及闭环系统的稳定性,研究PID控制参数对主动电磁轴承-刚性转子系统加速特性的影响以及H∞鲁棒控制器下转子系统加速特性对系统参数的不敏感性。最后,进行PID控制和H∞鲁棒控制条件下主动电磁轴承-刚性转子系统加速特性的仿真分析及实验。结果说明,PID控制参数变化对转子系统加速特性的影响,而H∞鲁棒控制下主动电磁轴承-刚性转子系统过临界的加速特性几乎不受加速度的影响,这与PID控制下传统转子系统的加速特性存在明显差异。

The acceleration response is a significant dynamic characteristic of active magnetic bearings(AMBs)-rigid rotor system.Currently,the research mainly focuses on the steady state characteristics of AMBs-rigid rotor system,and there are few studies on the acceleration characteristics.In this paper,taking AMBs-rigid rotor system as the object,the acceleration characteristics caused by different imbalance mass under PID controller and H∞robust controller were studied.Firstly,the dynamic equation of AMBs-rigid rotor system in the process of accelerating motion was established.Then,the design principle of PID controller and H∞robust controller and the stability of closed loop system were analyzed.Meanwhile,the influence of PID control parameters on the acceleration characteristics of AMBs-rigid rotor system was studied.Because of strong robustness of H∞robust controller,the acceleration characteristics are not sensitive to the system parameters.Finally,simulation and experimental results verified the acceleration characteristics of AMBs-rigid rotor system under PID control and H∞robust control.It is shown that the change of PID control parameters affects the acceleration characteristics of the rotor system,while the acceleration characteristics of the AMBs-rigid rotor system by H∞robust control are almost not affected by the acceleration,which is quite different from the acceleration characteristics of PID control and traditional rotor system.