A Study of Resonance Tracking Control for Langevin Typed Piezoelectric Vibrator

Phase Control under Variable Voltage

Abstract

Accurate dynamic control of Langevin typed ultrasonic vibrator has been just achieved. In the former report, the fluctuation of the drive current in thestate of resonance was indicated. The reason of the phenomena is clarified in this report and improved successfully. Furthermore, a PWM power supply was prototyped to obtain modulated drive voltage, which enables variable speed of vibration while keeping state of resonance.