四音叉定子驱动的压电旋转电机动力学特性

Dynamics Characteristics of Piezoelectric Rotating Motor Driven by Four-forked Stator

提出基于四音叉式定子驱动的旋转超声电机,选定定子的一阶面外弯振与二阶面内弯振为工作模态,复合形成旋转运动。阐明了电机驱动机理,基于频率一致性优化得到音叉杆尺寸为24mm×4.2mm×5mm,公共部分尺寸为12mm×12mm×3mm。建立电机的有限元(FEM)模型,对电机进行谐响应分析,排除激励时产生干扰模态。采用激励信号幅值为250V、频率为28000Hz对电机进行瞬态分析,得到动足的x、y、z向振幅分别为1.4μm、0.8μm和1.2μm。对电机进行运动特性分析,验证了该旋转电机具有良好的调频、调压、调相特性。

A rotary ultrasonic motor driven by four-forked stator is proposed. The first-order out-of-plane bending vibration and the second-order in-plane bending vibration of the stator are selected as the working modes to form a rotational motion. The driving mechanism of the motor is clarified. Based on the frequency consistency optimization, the tuning fork rod size of 24 mm×4.2 mm×5 mm and the common part size of 12 mm×12 mm×3 mm are determined. The FEM model of the motor is established, and the harmonic response analysis of the motor is performed to eliminate the interference mode when the excitation is generated. The transient analysis of the motor is carried out with an excitation signal amplitude of 250 V and a frequency of 28 000 Hz, and the x, y and z-direction amplitudes of the moving foot are 1.4 μm, 0.8 μm and 1.2 μm respectively. The motion characteristics of the motor are analyzed, and it is verified that the rotating motor has good frequency modulation, voltage regulation and phase modulation characteristics.