行波型超声电动机定子振动模型及其驱动设计

ANALYTICAL MODEL OF STATOR VIBRATION FOR TRAVELLING-WAVE ULTRASONIC MOTOR AND ITS DRIVER DESIGN

利用复合梁振动理论对典型结构的行波型超声波电动机(TWUSM)的振动特性进行了研究。根据定子结构的特点,将定子简化为一系列简支梁,由此建立了描述定子在逆压电效应作用下的强迫振动模型。此外,该模型还考虑了粘滑阻尼转矩和外部阻尼力的影响。最后借助于广义模态方法对该方程进行了求解,从而获得了在不同控制变量和不同结构参数下TWUSM的振动特性。为验证模型的准确性,设计制作了一台TWUSM样机和专用驱动器。样机试验结果与模型的仿真结果具有较好的一致性,从而验证了模型的有效性。

Research is done on vibration behavior of traveling-wave ultrasonic motor (TWUSM) by means of composite beam vibration theory. The stator is simplified to a series of simply supported beams according to the feature of configuration. A forced vibration beam's equation is then formulated which considers the external moment produced by the applied voltage with the aid of piezoelectric ceramics by means of inverse piezoelectric effectiveness. Also the viscous damping moment and external damping force are added to this equation. The equation is solved based on model expansion method. To validate the effectiveness of this model a prototyped motor is manufactured and tested. Experimental results show good agreement with those of calculation.