A piston piezoelectric (PZT) pump has many advantages for the use of light actuators. How to deal with the contradiction between the piston amount and oil delivery quality is an essence when designing the pump. In order to depress the pressure pulsation and flow pulsation in a single-piston PZT pump, a two-stage attenuator is proposed. It involves an elastic cavity group and an unloading valve. Unsteady flow inside the pump is numerically calculated and analyzed to reveal its delivery characteristic in the whole pumping cycle. The distributing process of the passive valves is obtained through the dynamic mesh technique. Influences of key design and operation factors on the delivery performance of the pump are analyzed. The results indicate that the flexible cavity group and the unloading valve arranged at the delivery port can reduce the flow pulsation by 45%. The design can effectively provide stable flow for the actuator in a certain frequency range.

活塞压电 (PZT) 泵在使用轻型致动器方面具有许多优势。如何处理好活塞量与出油质量之间的矛盾，是设计泵时的一个重点。为了抑制单活塞PZT泵中的压力脉动和流量脉动，提出了一种两级衰减器。它包括一个弹性腔组和一个卸荷阀。对泵内的非定常流动进行数值计算和分析，揭示其在整个泵送循环中的输送特性。被动阀的分布过程是通过动态网格技术获得的。分析了关键设计和运行因素对泵输送性能的影响。结果表明，柔性腔组和布置在出油口的卸荷阀可以减少45%的流量脉动。该设计可以在一定的频率范围内有效地为执行器提供稳定的流量。