大力矩径向驻波型超声波电机有限元分析与实验研究

Finite element analysis and tests for a high torque radialstanding wave type ultrasonic motor

提出了一种大力矩径向驻波型超声波电机,在实现电机大力矩输出的同时保持结构紧凑的特点。首先设计并分析了电机的结构和工作原理,采用有限元法分析了电机定子的振动特性。接着制作了超声波电机样机,样机直径为32 mm。采用激光测振仪测量了定子的共振频率及径向振动的振幅,测量结果与理论分析结果相吻合。最后,搭建了电机输出特性测试平台,测量了电机在不同电压下的转矩-转速特性。实验测试结果显示,定子工作模态的共振频率为73.3 kHz,当施加的电压幅值为100 V、频率为74 kHz时,电机的空载转速为45 r/min,堵转力矩达到0.41 N·m。与其他同尺寸的超声波电机相比,所提出的径向驻波型超声波电机具有更大的堵转力矩。

A high torque radial standing wave type ultrasonic motor was proposed to realize large torque output and keep compact structure feature.Firstly,the motor structure was designed and its working principle was analyzed.The finite element method was used to analyze its stator vibration characteristics.Then a motor prototype with diameter of 32 mm was fabricated.Its stator’s resonance frequency and radial vibration amplitude were measured with a laser vibrometer.The measurement results agreed well with theoretical analysis ones.Finally,a test platform for measuring the motor’s output characteristics was constructed and torque-speed characteristics of the motor under different voltages were measured.The results showed that the resonance frequency of the stator working mode is 73.3 kHz;when applied voltage amplitude is 100 V with frequency of 74 kHz,the motor’s no-load speed is 45 r/min,and its blocking torque reaches 0.41 N-m;compared to other ultrasonic motors with the same sizes,the proposed motor has a larger blocking torque.