Study and implementation of a 15-W power amplifier for piezoelectric actuator

This paper implements a 15-W power amplifier for piezoelectric actuators which is mainly composed of a flyback converter and a power operational amplifier. The flyback converter offers a variable DC output voltage to the power operational amplifier, which outputs an amplified sinusoidal wave with a voltage gain of 20 V/V and a DC bias of 100 V to drive the piezoelectric actuator. The output voltage of the flyback converter which varies with the amplitude of the input signal can reduce the power losses, and the whole power conversion efficiency of the amplifier can thus be promoted up to 40%. From the experimental results, the implemented prototype possesses some features, such as a nearly constant output-to-input voltage gain, a high slew rate, a high input impedance, a low output impedance, and low output voltage ripple.