径向主动式电磁轴承及其数字控制系统的研究

【作者】 郑思铭；

【导师】 向凤红；

【作者基本信息】 昆明理工大学 ， 控制理论与控制工程， 2007， 硕士

【摘要】 电磁轴承是一种利用磁场力将转子稳定悬浮在空中的一种新型机电产品，它具有无摩擦、无润滑、允许转速高、动态特性可调整等优点，越来越受到科技界和企业界的重视。电磁轴承的应用是一种高新技术，涉及到电磁学、机械学、转子动力学、控制理论和计算机科学等众多领域。本文分析了电磁轴承的工作原理，其中检测部分采用无传感器转子位移自检测模式，这样既减少了成本，也优化了控制性能，是未来的发展方向之一。之后推导了单自由度情况下电磁力与转子位移之间的关系，建立了其数学模型。对此模型分别采用传统的PID控制和改进的控制方法，在Matlab平台上进行仿真，并对二者的仿真结果进行了分析。比较发现，改进后的控制由于结合了模糊控制和PID控制，能使系统响应的超调量减小，反应时间加快，而且可对参数进行自适应调整，对电磁轴承等非线性系统有非常好的控制效果。在硬件仿真方面，首先由模拟对象电路板将被控电磁轴承转换为相应的模拟对象，再用控制器电路板对其进行控制，两块电路板均采用了C8051F120芯片，最后将控制结果输入到上位机进行观察。发现控制效果与Matlab的仿真效果相近，可以满足磁悬浮轴承的性能要求。更多还原

【Abstract】 Active magnetic bearings(AMB) is a new kind of product applied in rotating machinery ,which can use controllable electromagnetic force to support a rotor freely. Compared with the conventional rolling element or journal bearings,it is non-friction and need no lubrication even when operating in high speed ,and its dynamical property is adjustable,so it attract the attention of science and enterprise fields.The application of AMB is high technology which concerning many fields such as magnetics , mechanics, rotor dynamics , control theory and computer science.This paper analyses the working principle of AMB firstly , then derive the relationship between electromagnetical power and rotor displacement under the single degree of freedom,and a mathmatical model is established at last.In control system, the monitoring part use no sensor but electromagnet itself to monitor the rotor displacement.This is a trend in AMB development because it not only cut down whole cost but also optimize control effect.As for the mathmatical model,there were two control algorithms.One is conventional PID and the other is improved one which combines the advantages of PID and fuzzy controller. Because of the advantages, it make overshooting number smaller and reaction time shorter ,also can adjust the parameter by itself, so this algorithms is very suitable for non-linear system.After simulinking on matlab platform, simulating on real hardware is needed. First of all, the controlled object of AMB can be transformed into simulative object by an electrical circle board , then use another one to control the simulative object. The two electrical circle boards also use the chip C8051F120. The results putting in computer show that the control effect is almost same as simulinking on matlab and can meet the need of AMB control system.更多还原