液压放大式PZT-DDV建模与控制仿真

研制基于液压位移放大原理的压电陶瓷直接驱动伺服阀(PZT-DDV,Piezoelectric-Direct Drive Valve),实现大流量高频响的要求.分析其结构特点,建立系统数学模型,基于AMESim 和Simulink的协同仿真环境,对其进行仿真控制研究.采用AMESim建立了PZT-DDV的模型和虚拟液压测试系统,利用Simulink建立了数字控制器模型,通过接口组成协同仿真环境.针对PZT-DDV的迟滞、摩擦和液压位移放大结构的负载敏感特性,采用前馈控制改善迟滞,提高动态响应.基于LuGre摩擦力模型以及密闭腔压力监测,采用自适应backstepping方法实现摩擦及负载变化对放大机构输出位移的扰动补偿.仿真结果表明:前馈控制提高了系统的动态性能,自适应backstepping控制方法提高了系统的稳态控制精度.

Modeling and control simulation of PZT-DDV using hydraulic amplification

A servo valve direct driven by piezoelectric actuator (PZT-DDV) using hydraulic amplification was researched. It takes advantage of the higher bandwidth and larger flow rate. The actuary model was built. The characteristic of PZT-DDV was investigated based on the co-simulation environment of AMESim and Simulink. By using AMESim the PZT-DDV nonlinear model and hydraulic environment have been set up. By using Simulink the digital controller model had been set up. LuGre friction model was used to estimate the friction force, feed forward and adaptive back stepping control was investigated to improve the hysteresis, friction and load sensitive characteristic of PZT-DDV. The simulation results demonstrate that the steady precision can be improved by the adaptive back stepping control and the dynamic performances can be improved by the feed forward control.