A design study of ultrasonic motor drive

An ultrasonic motor (USM) has been widely used in a great variety of applications since it exhibits several advantages over the conventional electromagnetic motor such as high torque at low speeds, light weight, quiet operation, no electromagnetic interference (EMI), and high holding torque without supply. In this paper, the basic principle of USM drive is presented using the commercial D6060 driver for USM modeled USR60-E3 as a sample test. Its equivalent circuit model and parameters, and speed control are also explained. The commercial D6060 driver for USM modeled USR60-E3 is also tested and some experimental results are included. The new driving circuit for USM is proposed and the series inductance is designed. This circuit would improve the speed controlling easier and smoother than D6060 driver, using the manually adjusted potentiometer. Some preliminary simulation results are presented to validate the proposed driving circuit with the designed series inductance.