双振子驻波直线超声电机的设计与建模

发布时间：2018-01-17 13:05

本文关键词：双振子驻波直线超声电机的设计与建模　出处：《南京航空航天大学》2014年博士论文　论文类型：学位论文

【摘要】：驻波直线超声电机是最具代表性的直线超声电机,它在航天、医疗、精密仪器仪表、机器人等领域中显示了广阔的应用前景,得到了越来越广泛的关注。目前的驻波直线电机虽然外形多种多样,但其最基本的工作原理仍较单一,且在电机的整机建模上一直进展缓慢,不利于其研究的进一步发展。本文提出了一种新原理的驻波直线超声电机的设计方案,设计加工了样机,并建立了该电机的整机动力学模型和整机热力学模型。本文主要的研究内容和成果综述如下:1.简要地介绍了直线超声电机的发展历史,并重点介绍了驻波直线超声电机结构设计和理论建模的研究现状。针对驻波直线超声电机研究的不足之处,明确了本课题的研究目标。2.提出了双振子驻波直线超声电机的设计方法。该方法的主要创新在于:将传统驻波直线超声电机定子的复杂耦合模态振动解耦成两个简单的独立模态振动,并分别交由一个单模态振子来实现。由于两振子是独立设计的,因此可对它们的结构分别进行调整,使电机两项模态频率一致。因此,该设计方法可简化直线超声电机的设计。根据该方法,设计加工了一个基于杆结构的双振子型驻波直线超声电机。在100Vp的电压激励下,样机最大推力、速度、功率分别达到了47N,0.43m/s和7.85W。3.探讨了两振子的固有频率差对电机输出性能的影响规律。在此基础上,通过优化电机结构,控制该电机两振子在自由边界条件下的固有频率,电机的输出性能得到了改善。实验结果表明:对该样机而言,当自由边界条件下定子的二阶纵振固有频率高于动子一阶纵振固有频率73 Hz时,样机最大推力、速度和功率分别达到了64.2 N,0.76 m/s和17.4 W;最大推重比达到23.7,最大效率达到39.6%。4.建立了该双振子驻波直线超声电机的动力学模型。该动力学模型主要包括:定子与动子的接触模型、定子的振动模型、动子的振动模型和定子与动子间摩擦传动模型。利用该动力学模型可以得到定子和动子的模态特性、振动响应、以及电机直线运动的位移、速度与时间的关系等。在建模过程中,考虑了定子与动子接触的非线性因素。5.基于动力学模型,利用MATLAB编程,进行了振子模态特性、电机输出特性和电机瞬态特性的仿真,实验结果与仿真结果一致。在仿真的基础上,(1)提出一种电机结构设计算法,编写了程序并设计了人机交互界面,该程序快速准确,方便该型电机的结构设计;(2)提出一种提高电机输出性能和效率的方法,该方法通过实验得到了验证。6.分析总结了该电机运行中温度上升的原因,详细计算了导致电机温度上升的损耗。在计算的结果上,利用ANSYS对该电机进行了热力学仿真,得到了电机热稳态下的温度场分布,以及电机上任一点的温度—时间变化关系。该研究为进一步探讨超声电机热源优化问题提供了分析方法。
[Abstract]:Standing wave linear ultrasonic motor is the most representative linear ultrasonic motor, it has shown a broad application prospect in aerospace, medical treatment, precision instrument, robot and other fields. The standing wave linear motor has been paid more and more attention. Although it has a variety of shapes, its basic working principle is still relatively simple, and the progress in the whole machine modeling of the motor has been slow. In this paper, a new design scheme of standing wave linear ultrasonic motor is proposed, and the prototype is designed and processed. The dynamic model and thermodynamic model of the motor are established. The main research contents and results are summarized as follows: 1. The development history of linear ultrasonic motor is briefly introduced. The research status of the structure design and theoretical modeling of standing wave linear ultrasonic motor is introduced, and the deficiency of standing wave linear ultrasonic motor research is pointed out. 2. The design method of double vibrator standing wave linear ultrasonic motor is put forward. The main innovation of this method lies in:. The complex coupling mode vibration of the stator of traditional standing wave linear ultrasonic motor is decoupled into two simple independent modes. Because the two vibrators are designed independently, their structures can be adjusted separately to make the two modes frequency of the motor consistent. This design method can simplify the design of linear ultrasonic motor. According to this method, a double-vibrator standing wave linear ultrasonic motor based on rod structure is designed and manufactured. Under the voltage excitation of 100Vp, the maximum thrust of the prototype is obtained. The speed and power reach 47NV 0.43m / s and 7.85W.3.The influence of the natural frequency difference of the two oscillators on the output performance of the motor is discussed. On this basis, the structure of the motor is optimized. The output performance of the motor is improved by controlling the natural frequency of the two vibrators under the free boundary condition. The experimental results show that: for the prototype. When the natural frequency of the second order longitudinal vibration of the stator is higher than 73 Hz of the first order longitudinal vibration of the stator under the free boundary condition, the maximum thrust, velocity and power of the prototype are 64.2 N. 0.76 m / s and 17.4 W; The maximum push-weight ratio is 23.7 and the maximum efficiency is 39.6.4.The dynamic model of the double-vibrator standing wave linear ultrasonic motor is established. The dynamic model mainly includes the contact model between stator and mover. The vibration model of the stator, the vibration model of the rotor and the friction transmission model between the stator and the actuator can be used to obtain the modal characteristics, vibration response of the stator and the actuator, as well as the displacement of the motor's linear motion. The relationship between velocity and time, etc. In the process of modeling, the nonlinear factors of stator and mover contact are considered. 5. Based on the dynamic model, the modal characteristics of oscillator are carried out by using MATLAB programming. The simulation results of the output characteristics and transient characteristics of the motor are consistent with the simulation results. On the basis of the simulation, a motor structure design algorithm is proposed, a program is written and the man-machine interface is designed. The program is fast and accurate, and it is convenient for the structure design of the motor. A method to improve the output performance and efficiency of the motor is proposed. The method is verified by experiments. 6. The reasons for the temperature rise in the motor operation are analyzed and summarized. The loss caused by the temperature rise of the motor is calculated in detail. Based on the calculation results, the thermodynamics simulation of the motor is carried out by using ANSYS, and the temperature field distribution under the thermal steady state of the motor is obtained. And the relationship between temperature and time at any point on the motor. This study provides an analytical method for the optimization of ultrasonic motor heat source.
【学位授予单位】：南京航空航天大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TM359.4

【引证文献】