Piezoelectric hydraulic pump system dynamic model

A system dynamic model was developed for use in the design of piezohydraulic pumps. The model was implemented in MATLAB to predict the electrical/mechanical/fluid coupled behavior of the piezoelectric pump system. Model results were used in a performance assessment of a pumping system that was comprised of a stack actuator driven pump, accumulator, power supply, four-way valve, and hydraulic actuator. The model provided reasonable predictions of performance. Rate effects at higher voltage and frequency reduced pressure and flow rate performance. The heat generation of the piezoelectric stack actuator, flow resistance of the check valves, and compressibility of the fluid contributed to bandwidth limitations.