面内模态直线型超声电机的优化设计

利用矩形薄板面内2个不同模态作为工作模态的直线型超声电机，其频率一致性和压电单元的布置方式以及激励方式对电机的性能和效率有重要的影响。该文根据电机定子的位移振型和应变振型详细分析了压电陶瓷的布置方式和激励方式，并利用参数化有限元方法(finite element method，FEM)对定子结构进行优化设计。设计制作的样机，两相工作模态频率差为270 Hz，在电压峰峰值为350 V、驱动频率为44.16 kHz、预压力为50 N的情况下，电机最大空载速度为100 mm/s，最大输出力为3 N。

Optimum Design of a Linear Ultrasonic Motor Based on In-plane Modes

The frequency coincidence, mount position of piezoelectric ceramics and excited mode have very important effect on the performance of the motor using two different modes. Therefore, according to the first-longitudinal mode, the second-bending mode and its strain modes of the stator, this paper analyzed the installed position of the piezoelectric ceramics and excited mode and presented a new way to optimize the frequency compatibility of the two work modes using finite element method (FEM). The prototype was investigated by the experiment, the frequency difference of the two work modes is only 270 Hz, the maximum no-load speed of the motor achieves 100 mm/s and the largest output force achieves 3N at the case of the operation voltage is 350 V, driving frequency is 44.16 kHz and the pre-pressure is 50 N.