# Analysis of Ultrasonic Linear Motor Using the Finite Element Method and Equivalent Circuit

• Park, Jong-Seok (School of Electrical Engineering and Computer Science, Seoul National University) ;
• Joo, Hyun-Woo (School of Electrical Engineering and Computer Science, Seoul National University) ;
• Lee, Chang-Hwan (Electrical Engineering and Science Research Institute, Seoul National University) ;
• Jung, Hyun-Kyo (School of Electrical Engineering and Computer Science, Seoul National University)
• Published : 2003.12.01

#### Abstract

In this paper, a three-dimensional finite element method and construction of equivalent-circuit for a linear ultrasonic motor are presented. The validity of three-dimensional finite element routine in this paper is experimentally confirmed by analyzing impedance of a piezoelectric transducer. Using this confirmed finite element routine, impedance and vibration mode of a linear ultrasonic motor are calculated. Elliptical motion of contact point between vibrator and rail of the linear ultrasonic motor is shown for determination of contact points. By using the finite element method and analytic equations, characteristics of the linear ultrasonic motor, such as thrust force, speed, losses, powers and efficiency, are calculated. The results are confirmed by experiment. Finally, equivalent circuit parameters of the linear ultrasonic motor are obtained using the three-dimensional finite element method and analytic equations.

#### References

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