【作者】 肖丹；

【导师】 熊万里； 桂林；

【作者基本信息】 湖南大学 ， 机械工程（专业学位）， 2021， 硕士

【摘要】 永磁同步电主轴转子原理上不发热、效率高、功率密度高、惯量小、动态响应快、力矩特性硬,在高速/超高速精密磨削等领域应用广泛。但由于高速永磁同步电主轴“驱动器-电机-主轴-刀具-载荷”系统机电参数存在复杂的耦合作用,若系统参数匹配不当,将会引起电主轴输出转矩转速波动,导致系统工作的稳定性和加工质量下降。目前关于高速电主轴系统的机电耦合问题,在异步电主轴领域得到了较好解决,但尚未涉及到永磁同步电主轴,亟需研究解决。本文的研究工作如下:(1)开展8kW/80krpm的高速永磁同步电主轴电机电磁理论设计,基于ANSYS EM建立了高速永磁同步电主轴电机二维电磁场有限元分析模型,研究了气隙长度、定子槽口宽度等电磁设计参数对电机稳态性能的影响,确定了合理的参数选取范围。(2)根据驱动器变频调速调制工作原理、电机动力学和拉格朗日分析动力学理论,建立了高速永磁同步电主轴“逆变器-电机-主轴-砂轮-磨削载荷”系统的机电耦合动力学模型。针对模型特征,提出了基于龙格库塔的模型求解方法,实现了高速磨削永磁同步电主轴系统机电耦合过渡过程的定量仿真。(3)利用所建立的机电耦合模型和所提出的模型求解方法研究了电机参数、变频驱动器中逆变器参数和磨削载荷对电主轴输出电流、电磁转矩和转速以及砂轮扭转振动的影响,提出了抑制系统机电耦合振动的具体策略。研究表明:在给定参数范围内,通过合理增大气隙长度、减小定子槽口宽度、增大载波频率可以有效降低砂轮扭转振动,抑制系统机电耦合振动。(4)参与开发了8kW/80krpm电主轴样机并搭建了实验台。通过实验测得了电主轴空载时的电压值和振动量,与仿真结果进行了对比分析,电压值误差不超过10.35%,振动趋势和仿真基本一致,验证了电机电磁设计方案的正确性以及所建立的系统理论模型和方法的有效性。实验表明:该样机能运行在75krpm以内,且增大载波频率能有效抑制电主轴振动,实验所得规律与仿真分析结果较吻合。本文研究为高速/超高速永磁同步电主轴电机的开发设计和系统参数优化匹配提供了重要的理论方法和有效途径,同时提供了8kW/80krpm高速永磁同步电主轴的工程开发案例。更多还原

【Abstract】 Permanent magnet(PM)synchronous motorized spindles(PMSMS)have a wide range of applications in high-speed/ultra-high-speed precision grinding due to their heatless rotor in principle,high efficiency,high power density,low inertia,fast dynamic response and hard torque characteristics.However,due to the complex coupling of the electromechanical parameters of the "drive-motor-spindle-cutter-load" system of high-speed permanent magnet synchronous motorized spindles(HSPMSMS),improper matching of system parameters will cause fluctuations in the output torque and speed of the spindle,resulting in a decline in the stability of the system and the quality of processing.The current problems regarding the electromechanical coupling of high-speed motorized spindle systems have been better solved in the field of asynchronous motorized spindles,but have not yet involved PMSMS,which need to be studied and solved urgently.The research work in this paper is as follows:(1)The electromagnetic theory design of the 8kW/80 krpm high-speed permanent magnet synchronous electric spindle motor is carried out.A 2D electromagnetic field finite element analysis model of a HSPMSMS motor is established based on ANSYS EM.The influence of electromagnetic design parameters such as air gap length and stator slot width on the steadystate performance of the motor is investigated,and the reasonable parameters selection range are determined.(2)The electromechanical coupling dynamics model of the "inverter-motor-spindlegrinding wheel-grinding load" system of a HSPMSMS is established based on the working principle of drive frequency modulation,motor dynamics and Lagrange analysis dynamics theory.According to the characteristics of the model,Runge-Kutta method is adopted to realize the quantitative simulation of the transition process of the high-speed grinding PMSMS system.(3)The effects of motor parameters,inverter parameters and grinding load on the current,electromagnetic torque and speed of the motorized spindle and grinding wheel torsional vibration are investigated using the established electromechanical coupling model and the proposed model solution method.The strategies to suppress the system electromechanical coupling vibration are proposed.The study shows that,within the given parameters,increasing the air gap length,reducing the stator slot width and increasing the carrier frequency can effectively reduce the grinding wheel torsional vibration and suppress the system electromechanical coupling vibration.(4)The prototype 8kW/80 krpm motorized spindle is produced and the experimental bench is built.The voltage and vibration of the motorized spindle at no load are measured and compared with the simulation results.The error of the voltage value do not exceed 10.35%,and the vibration trend is basically consistent with the simulation results.The experimental results show that the prototype can run within 75 krpm,and increasing the carrier frequency can effectively suppress the vibration of the motorized spindle.The experimental results are consistent with the simulation analysis results.The research provides important theoretical methods and effective approaches for the development and design of high speed/ultra-high speed PMSMS motors and the optimal matching of system parameters.At the same time,it provides an engineering development case of 8kW/80 krpm HSPMSMS.更多还原