A Design Method of Traveling Wave Rotary Ultrasonic Motors Driving Circuit under High Voltage Using Single-Sided Hertzian Contact Forced Oscillator Model

Abstract

Traveling wave rotary ultrasonic motors (TRUMs) are widely used in various industrial processes due to their attractive features, such as compact structure, high accuracy, and fast response. However, the major limiting factors of the operational performance of TRUMs under high-voltage excitation are the nonlinear behavior caused by the nonlinearities of the piezoelectric materials and the friction between the stator and rotor of the motor. In this study, a nonlinear dynamics model and an identification method are presented to directly design the driver circuit for suppressing the nonlinear behavior under high voltage excitation. Firstly, by studying the time–frequency characteristics of the isolated electrode voltage, a single-sided Hertzian contact forced oscillator model of TRUMs is established, involving the nonlinearities of the piezoelectric material and friction. Secondly, a harmonic balance nonlinear identification is proposed in the time domain for TRUMs. The influence of the voltage and preload on the nonlinear phenomena is discussed. Lastly, a novel driver circuit is proposed to suppress the nonlinearities using feedback from the isolated electrode. Experiments showed that the total harmonic distortion decreased by 89.4% under 500 Vpp. The proposed drive circuit design method is used to find a high excitation voltage and preload to achieve greater motor output power.

A novel rotary ultrasonic motor based on multiple Langevin transducers: design, simulation, and experimental investigation

“…This type of ultrasonic motor has met the requirements for shortterm service in aerospace mechanisms. In order to improve the comprehensive performance of TRUSMs, scholars have made progress in structure [18,19], drive and control [20,21], theory [22,23] and so on. However, some inherent technical difficulties of TRUSMs are hard to break through.…”

A Micro Radial-Torsional Vibration Ultrasonic Motor Driven by Single-Phase Signal

“…Then the traveling waves on the stator driving interface or elliptical trajectories of particles on its surface are formed through the coupling of these vibration modes, thus promoting the rotation of rotor. Traditional traveling-wave rotary ultrasonic motors (TRUMS) [8][9][10][11][12], longitudinal torsional composite ultrasonic motors (LTUMS) [13][14], V-shaped linear ultrasonic motors [15][16] and disk ultrasonic motors are coupled by two vibration modes and driven by two-phase electrical signals. Although their output torques are large, the standards of structural design, piezoelectric ceramic performance and driving controller are high.…”