中文摘要：

为解决电机受传统时空相位限制的这一难题,针对超声电机的激振问题,采用能量方法建立了定子弹性动力学模型.应用解析方法研究了压电片的分组对称拓扑对弹性振动特性的影响,揭示了拓扑结构与行波及驻波之间的映射关系,得到了产生行波的一般条件.结果表明：采用满足该映射关系的工作波数、压电片个数及其分组可生成期望的波动响应;该映射关系提供了保证振幅最大的压电片最优分组方式.研究结果有利于优化激振方式,提高超声定子的激振效率.

英文摘要：

The vibration excitation of ultrasonic motor is examined in this paper. In order to improve the efficiency of the traditional motor,an elastic dynamic model of stator was developed by using energy method. The effect of grouping symmetric topology on vibration properties was analytically examined. The mapping relationships and conditions between the topology and traveling/standing wave were identified and the general conditions of traveling wave occurrence were obtained. The results imply that desired wave vibration can be aroused by using a suitable parameter combination satisfying the mapping relationships,where the parameters include the working wavenumber,number of piezoelectric patches and grouping pattern. Thus an optimized grouping pattern inducing remarkable amplitude is obtained. The results contribute to improve the excitation pattern and enhance the excitation efficiency of stator.