A New Type Of Self-excited Oscillation Drive Power Supply Design,

The ultrasonic motor(USM) is a new type of motor that has been developed in recent twenty years. It's different from traditional electromagnetic motors in principle. Ultrasonic vibration is excited by the converse piezoelectric effect of piezoelectric the rotor or moving of the slider is generated. USM is characterized by the low speed, high torque, simple structure and directly load-driving. It isn't disturbed by the electromagnetic field. USM can carry out self-hold without electric power. So the USM is widely applied in the fields of micro-machines, robots, precise instruments, spacecrafts and automobiles. As the increasing temperature, the frequency of USM will shift. It's very meaningful to do research on the new USM frequency tracking driving circuit.This thesis aims at the realization of auto-frequency-tracking for single phrase standing wave USM. And it studies theoretically and experimentally on the modeling, design, driving of it. The following are the chief research achievements and work of this thesis.1. The history and characters of USM, and the control method.2. The development of frequency tracking driving circuit of USM and the great significance of self-oscillating circuit are illustrated.3. The equivalent circuit of piezo-vibrator makes the self-oscillating circuit possible.4. Based on the principle of self-oscillating, the self-oscillating driving circuit is designed and made.5. The experiments of frequency scanning and performance-measuring of motor have been made. The results prove the circuit has the capability of auto-frequency-tracking.6. The driving circuit will be useful in miniaturization and integration...