A novel high energy density single-phase linear piezoelectric motor: design and experiment

Abstract

The circuit simplification and simple structure of piezoelectric motor have become a major trend at present. Therefore, a novel, miniaturized, single-phase driven piezoelectric motor is proposed. The suggested piezoelectric motor employs a bending vibration mode of the first order, which is inspired by the motion patterns of fish tail fins. First, the motor’s operational principle and structure are explained. By analyzing the relationship between the working frequency and amplitude of the motor and the output power, the key parameters of the motor are determined, and the structure size of the motor is calculated. Next, the FEM model of the stator is utilized to conduct transient analysis in order to examine the movement path of the driving foot. Symmetrical right-diagonal or left-diagonal motions are formed by the driving foot during the first bending vibration, creating oblique elliptical movements. Finally, a prototype is made and its vibration and mechanical characteristics are tested. At a frequency of 15.6 kHz, the motor’s highest speed without any load is measured at 31.2 mm/s. Both forward and backward performance is identical. When the motor is supplied with a voltage of 140 Vpp and a preload of 2 N, it achieves a moving speed of 4.2 mm/s at 15.6 kHz, with an output thrust of around 0.9 N.