Miniature Piezomotors, Resonant, Regenerative Switching Piezomotor Drive Amplifier

摘要

Piezoelectric actuatIrs and motors promise to deliver useful work at power densities an order of magnitude greater than that of their electromagnetic counterparts. The circuit concept developed is for a resonant, regenerative switching piezomotor drive amplifier that would efficiently transfer electrical energy that could be coupled into mechanical work through a piezoelectric actuator. The motor/amplifier system would operate at both electrical and mechanical resonances for the system. The amplifier's efficiency is estimated to be greater than 80% when driving a 1uF piezoelectric load with a 500 Vpk-pk signal. The available output power should be greater than 20 watts continuously from DC to 2.0 kHz. A prototype amplifier with +50% power efficiency is presently undergoing design debug and testing. Once operational, future amplifier refinements can focus on improved analog computation methodologies, mitigation of alignment and calibration difficulties, while trying to reduce sensitivity to actuator capacitance and improvements to output waveshape fidelity. Concurrently, a limited amount of effort was made towards miniaturization and optimization of two existing piezomotors. Improved models and experimental data will help enhance the future design of these prototype piezomotors.