【作者】 吕慎刚；

【导师】 蒋书运；

【作者基本信息】 东南大学 ， 机械制造及其自动化， 2006， 硕士

【摘要】 高速电主轴是高性能机床的核心部件,它将主轴电动机内置于机床主轴中,两者“合而为一”,因而具有结构紧凑、质量轻、惯性小、振动小、噪音低、响应快、易于实现主轴定位和准停等突出优点,在航空航天、汽车与摩托车、模具制造、轻工与电子工业和其他制造业获得越来越广泛的应用。新一代高速电主轴的工况特点是低速大转矩和高速大功率,预紧力可控是很有技术发展前途的新方向。确定最佳预紧力,实现电主轴在包含低速大转矩与高速大功率整个工作范围内动力学品质全局兼优是预紧力可控的基础。基于此,本课题提出了基于最佳预紧力电主轴振动控制技术。本文基于电主轴预紧力可控的思想,在普通电主轴的基础上设计了预紧力可控的电主轴;基于整体传递矩阵建模方法和滚动轴承分析理论,建立了主轴转子-轴承系统动力学模型,研究计算了电主轴系统的临界转速和主振型;考虑轴承阻尼效应,分析了主轴的动刚度,在一定准则下给出了在动力学范围内电主轴系统的最佳预紧力;基于单片机设计了电主轴预紧力控制系统包括控制器和功率放大器以及相应的外围电路,并对控制系统进行了调试,为电主轴最佳预紧力的实现奠定了基础。最后研究了以磁轴承作为支承的磁轴承电主轴的鲁棒控制。建立了五自由度磁轴承电主轴的动力学模型,并阐述了基于DSP的磁轴承电主轴数字控制系统;以存在模型不确定性的径向磁轴承转子系统为研究对象,设计了μ综合鲁棒控制器,借助Matlab工具对设计的控制系统进行了仿真,结果表明控制系统对模型不确定性有很好的稳定鲁棒性和性能鲁棒性。更多还原

【Abstract】 High speed motor spindle is the key functional component of high precision CNC machine tool, in which the main spindle motor is mounted to the spindle and become a complete built-in spindle unit. Therefore it has been paid more attention for its compact configuration, light mass, little inertia, small vibration, low noise, fast response and other advantages, and also for its wide application such as aeronautics and astronautics, automobile, mold manufacture and other manufacture fields. With the development trend towards high torque at low speed and high power at high speed, preload control is a brand-new direction with good technology future. It is of importance to obtain optimum preload and ensure the dynamic quality in whole work condition including high torque at low speed and high power at high speed, which is the foundation of preload control. As a result of this, vibration control of high speed motor spindle based on optimum preload is presented in this paper.Firstly, motor spindle is designed on the basis of preload control. And whole transfer matrix method and rolling bearing theory is used to establish the dynamic model of rotor-bearing system and analyze the critical rotation speed and main mode. Furthermore, spindle stiffness is calculated with considering bearing damp effect, and optimum preload is given under some criterions in whole work condition.Secondly, preload control system for motor spindle is designed based on microcontroller including controller, power amplifier and so on. And it has been debugged, which lays the foundation for realization of optimum preload for motor spindle.Finally, robust control for motor spindle with active magnetic bearing (AMB) is studied in the paper. The dynamic equations of the five-degree-of–freedom motor spindle with AMB are built, and digital control system for motor spindle with AMB is presented based on DSP. On the basis of analyzing racial AMB system with system modeling uncertainty, aμrobust controller is designed by introducing fictive uncertainty. The simulative waveforms of control system are given under different instances by using Matlab. The results of simulation show that the AMB robust control based onμsynthesis theory has strong robustness to system model uncertainty and the external disturbances can be controlled effectively.更多还原