| Title |
A Study on the Novel Control Method to Drive the Traveling Wave Type Ultrasonic Motor adapting the Impedance Angle Control |
| Authors |
이을재(Lee, Eul-Jae) ; 김영석(Kim, Yeong-Seok) |
| Keywords |
Ultrasonic motor ; Impedance angle ; Phase difference |
| Abstract |
In this paper, we proposed a novel control method which uses the internal impedance angles as a control parameter to drive traveling wave type ultrasonic motor. An impedance characteristic of the ultrasonic motor is obtained by analysis of the equivalent circuits including the external inductor used to generate the coupled resonance. The phase angle of internal impedance to achieve optimal control performance is derived. For the tracking of impedance angle, an information of phase difference is obtained from the applied voltage and current. The high speed phase difference detector is designed to monitor the phases of ultrasonic motor. The effectiveness of the proposed control scheme is clarified by experiments. |