Ultrasonic Motors

1. A
Seminar
on
ULTRASONIC MOTORS
By
Y.CHAKRI VENKATA DINESH
(13HM1A0217)
Department of Electrical And Electronics Engineering
Annamacharya Institute of Technology and Sciences
31/03/17 1Dept.of EEE,AITS-KADAPA

2. Contents
Introduction
Drawbacks of Electro Magnetic Motors
Principle of operation
Construction
Working
Characteristic features
Advantages & Disadvantages
Applications
Conclusion
31/03/17 Dept.of EEE,AITS-KADAPA 2

3. Introduction
A motor is a machine which converts electrical energy
into mechanical energy.
UltraSonic Motors (USMs) are next generation motors.
The first USM was developed by Russian scientist in
1965
USMs are characterized by the absence of noise during
operation , high accurate speed and position control etc.,
31/03/17 Dept.of EEE,AITS-KADAPA 3

4. Drawbacks of Electro Magnetic Motors
 Noisy operation
Less efficiency
High motor temperatures
High cost
Increased size with increase in rating of motor
31/03/17 Dept.of EEE,AITS-KADAPA 4

5. Principle of operation
USM works on the principle of Converse Piezoelectric
Effect.
31/03/17 Dept.of EEE,AITS-KADAPA 5
(a) When applied DC voltage has same polarity
(b) When applied DC voltage has opposite polarity
(c) When AC voltage is applied

6. Construction
31/03/17 Dept.of EEE,AITS-KADAPA 6

7. Piezoelectric Ceramics
31/03/17 Dept.of EEE,AITS-KADAPA 7

8. Working
When high frequency voltage (>20 KHz) is applied
piezoelectric material vibrates.
There are two power transformations involved in running
of USM.
(a)Conversion of Electrical energy into
mechanical vibrational energy
by Inverse Piezoelectric Effect.
(b)Vibrational energy of stator is transformed
into continuous moving energy of rotor due to
frictional interaction between stator and rotor.
31/03/17 Dept.of EEE,AITS-KADAPA 8

9. Characteristics of USM
Simple construction
Absence of magnetic action
Low Speed
High Torque
Quick response
Noiseless
Compact
Lightweight
31/03/17 Dept.of EEE,AITS-KADAPA 9

10. Advantages of USM
Low AC voltage excitation
High torque at low speeds
Short time response
Ultra small size can be easily miniaturized
Dust free
Noiseless operation
High efficiency
High torque/weight ratio
No magnetic interference
31/03/17 Dept.of EEE,AITS-KADAPA 10

11. Disadvantages of USM
Piezoelectric materials are expensive
Requires high frequency power supply (>20 KHz)
Ultrasonic noise occurs
Due to friction life of motor reduces
31/03/17 Dept.of EEE,AITS-KADAPA 11

12. Applications
Auto focusing & optical zooming in digital cameras
Automatic wrist watches
Power windows
Roll screen motor for automatic open & close actions
Actuators for VCRs & CD players
 Robotics
Wall clocks
Ultrasonic welding
31/03/17 Dept.of EEE,AITS-KADAPA 12

13. Conclusion
The above mentioned
advantages and applications concludes scope
of USMs in day - to -day life.
However, disadvantages
brings up need for further researches in fields.
31/03/17 Dept.of EEE,AITS-KADAPA 13

14. 31/03/17 Dept.of EEE,AITS-KADAPA 14

15. 31/03/17 Dept.of EEE,AITS-KADAPA 15
Any
Queries??