【作者】 董迎晖；

【导师】 赵韩；

【作者基本信息】 合肥工业大学 ， 机械设计及理论， 2015， 博士

【摘要】 超声电机因具有传统电磁电机所无法拥有的一些优点而在某些驱动应用领域有着特别的优势,国内外研究者对这种电机进行了大量研究,特别是对行波型超声电机。这些研究多集中于：基于行波型电机基本驱动原理开发新型行波型超声电机；或者从电路、材料等方面分析电机输出性能。这种割裂式的研究方式存在一定的不足,本论文在安徽省自然科学研究基金资助下,深入研究行波型超声电机驱动原理,并基于驱动原理研究超声电机输出特性,在此研究结果基础上设计两种新型行波型超声电机,以验证理论分析的结果与结论。基于波动与振动理论研究弹性体内行波的产生与特点。论文采用理论分析与仿真手段,研究弹性体内行波产生的机理及激发条件。结果表明：兰姆波与梁弯曲行波是两个不同边界、不同属性的行波,其中弹性梁弯曲行波是单一模式,较易激发出单一行波。在弹性梁中可以直接激励产生行波,也可以采用驻波模态叠加法产生行波。行波可以使定子上质点按椭圆轨迹运动,椭圆运动轨迹特点直接影响电机输出特性。论文从理论上研究超声电机定子表面质点椭圆运动轨迹特点,将定子质点椭圆运动分解为有效椭圆运动和径向直线运动。其中,有效椭圆运动直接驱动转子,而直线运动使定、转子产生相对滑动而产生能量损耗。这个结论是后面Hula-hoop型超声电机的研究设计的理论基础。由于超声电机是一个机电耦合系统,论文从机电转换过程中的能量损耗着手,从能量角度研究超声电机效率问题。通过对压电振子系统方程的推导,将压电振子力系数表示为材料力系数与结构力系数的乘积。其中结构力系数与超声电机能量损耗直接相关,从而影响超声电机效率。采用仿真手段,验证了环形和圆柱体行波型超声电机的几何结构对结构力系数的影响。结果表明,通过改变定子的结构力系数,可以提高电机的效率。以上研究结果与结论可以应用于行波型超声电机的研究设计中。论文基于模态叠加法产生行波的原理,改进兰姆波弹簧定子超声电机,设计了新型的弹簧定子行波超声电机；根据定子质点椭圆运动分解原理,设计采用中点驱动的Hula-hoop行波型超声电机,并基于结构力系数法,对电机进行拓扑优化和参数优化设计。仿真结果表明两种电机性能都得到提升,也证明本论文文理论研究成果的正确性和实用性。更多还原

【Abstract】 The Ultrasonic Motors are expected to apply in some driving applications because they have some advantages which the traditional mangnetic motors can not have. Domestic and foreign scholars have done many researches on this kind of motor, especially on the traveling ultrasonic motor. Most of the researches have focused on developing new type of traveling ultrasonic motor based on the basic driving principle, and studying the performance of motor from the standpoint of electric circuit and materials. There exist certain deficiencies of the ways metioned above due to sperating the performance from the driving principle of USM. This dissertation further research the output performance of the USM based on the driving principle of traveling wave USM. Then two new types of traveling wave ultrasonic motors are designed on the base of the research achievments shown in this paper.The generation and characteristic of the traveling wave are analysed based on the theory of wave and vibration in elastic body. The activating mechanism and condition of traveling wave in, elastic body are studied in this dissertation using theoretical and simulation method. The results show that lamb wave and beam bending wave are two different kinds of traveling wave which have different boundary, and characteristics. The beam bending wave owns some advantages such as single mode, easily activating pure traveling wave. The traveling wave can be activated in elastic beam by means of superposition method with modal standing wave, and also can be produced directly.Travelling wave can make particle move on an elliptical locus and the shape of the ellipse trajectory directly affect the motor output characteristic. The characteristics of the particle ellipse trajectory on the stator surface are analysed theoretically in this dissertation.The elliptical motion of particles is decomposed into the effective elliptic motion and the radial linear motion. The effective elliptical motion drives the rotor directly, and the linear motion produces relative sliding between the stator and rotor, and thus produces energy loss. The reseach results will be the theoretical supports of the Hula-hoop type ultrasonic motors.Ultrasonic motor is an electromechanical coupling system, so the energy loss in the process of transformation between the mechanical field and electrical field can be analyzed and the efficiency of ultrasonic motors can be researched from the perspective of energy. The Electromechanicalcoupling equation of the vibrator is derived, and the piezoelectric vibrator force coefficient can be expressed as the product of the material force coefficient and the structure force coefficient. The structure force coefficient is directly related to the energy loss of ultrasonic motor, which affect the efficiency of motors. By means of simulation, it is verified that the structure force coefficient can be decreased by changing the geometry of the stator, for example, the ring-type and cylinder traveling ultrasonic motor. The results show that the efficiency of the motor can be improved by changing the structure force coefficient.The conclusions and results in this dissertation can be used in the design of traveling wave type ultrasonic motors. A new type of spring stator traveling wave ultrasonic motor is designed to improve the lamb wave spring stator ultrasonic motor using the mehod superposition by standing waves. According to the principle of decomposition of elliptic motion, a new type of Hula-hoop traveling wave ultrasonic motor is designed driving rotor by axial midpoint of the cylinder and the topology and some parameters of the stator is optimized based on the structure force coefficient method. The results show that the performance of both motor is improved, which verify the theory provided in this dissertation.更多还原