Characterization of a piezohydraulic actuator

Abstract

The PiezoHydraulic Pump (PHP) used in this work currently uses proprietary check valves that allow the PHP to be operated at 1 kHz. At a bias pressure of 500 psi and operating voltage of 1 kV, the PHP produces a mechanical power output of 46 W. The PHP was baseline tested using both the proprietary valves (internal) and external commercial passive check valves. Using the external valves at a bias pressure of 80 psi, the PHP was tested at various frequencies. At an operating frequency of 150 Hz, the maximum flow rate was 0.91 cc/s, while at 125 Hz, the maximum mechanical power output was 0.18 W (0.64 W/kg). This significant decrease in characteristics can be attributed to an increase in system compliance by moving the valves external to the pump housing and possible air entrapment within the chamber.

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