电液谐振式高频疲劳试验台动态特性研究

针对由单出杆液压缸与二位三通2D阀组成的电液谐振式高频疲劳试验台，因单出杆液压缸无杆腔与2D阀相连，有杆腔恒通油源。而2D阀突破常规电液伺服阀频宽极限，具有宽频带、高频响等特点，通过改变阀芯旋转速度及阀口轴向开度，可对系统分别进行变频、变幅控制。对采用2D阀控制技术的电液谐振式高频疲劳试验台建立数学、仿真模型，并对该试验台谐振工况进行仿真与实验研究，结果表明该系统谐振工况输出位移（载荷力）与激振力大，消耗外界功率低。

Study on the dynamic characteristics of electro-hydraulic resonant fatigue test rig

Electro-hydraulic resonant fatigue test rig is mainly composed of an asymmetric cylinder and a two-way three-position two-dimensional high rotational valve (Abbr. 2D valve). With this, the change of natural frequency of the electro-hydraulic fatigue test rig can be achieved by changing the initial length of the non-rod chamber of the asymmetric cylinder. Thanks to its broad bandwidth and high-frequency, 2D valve outperforms conventional electro-hydraulic servo valves which are constrained by bandwidth limit. The system’s frequency and amplitude can be controlled by changing the rotation speed of the valve spool and axial opening size. The paper establishes mathematical and simulation models for the variable resonant electro-hydraulic fatigue test rig which uses 2D valve control technology. Simulation and experimental studies of the test rig’s resonant working condition are also conducted. The results show that, when the fatigue test rig is working at resonant condition, the output waveform of the displacement (load force) and the exciting force is better, and the energy consumption is lower.