Temperature Study of Standing Wave Ultrasonic Motor

The standing wave ultrasonic motor (SWUSM) utilizes two resonant modes to enhance stator motion. The less the frequency separation between two resonance modes, the faster the speed of standing wave ultrasonic motor. Besides USM manufacturing variation, we found that the frequency separation is significantly influenced by the PZT temperature. In this paper, the experimental data was used to establish a transfer function that describes this relationship. This transfer function, in conjunction with the PZT temperature difference from the surroundings and the operating temperature range of the electrical device, can be used to determine the optimal frequency separation.