A High-voltage and High-power Amplifier for Driving Piezoelectric Stack Actuators

Abstract

Aiming at the strong capacitive impedance of piezoelectric stack actuators, the principle to improve the dynamic performance of piezoelectric stack actuators through increasing the peak values of the output current and output power of power amplifiers are explored. Based on the error-amplified principle, the method that enlarges the output voltage of the dynamic power amplifiers through using a high-voltage operational amplifier in series with the power booster section, as well as the method that improves the peak values of the output current and output power through paralleling multiple power booster units utilizing the class AB quasi-complementary symmetry power amplifier circuits, are proposed and analyzed. Utilizing the proposed principle and method, a high-voltage and high-power amplifier for driving piezoelectric stack actuators is developed, simulated, and tested. The research results indicate that the developed power amplifier not only can break through the limit that each single power booster unit can only achieve the power output <125 W, but also can disperse the current and power averagely among the power booster units in parallel, which are beneficial to realizing the high power output with good static and dynamic performance and enhancing the reliability of the power amplifier.