Based on the theory of an electro-hydraulic dynamic system and a nonlinear relation between pressure and flow,a mathematical model of the electro-hydraulic vibration exciter was established first.The analytic solutions to excited waveforms were given under the actions of two typical waveforms,such as sine wave and triangle wave.Then the calculations of the waveform distortion rate were carried out.Finally,the theoretical analysis results were validated by the vibration experiments.The experimental results reveal that the vibration wave peak moves to lateral side and the wave trough moves to medial side under the actions of triangle wave.This is mainly because of the changes of the direction of elastic load.The extent of deviation depends on the throttling areas of the valve.When it reaches to a certain threshold,the pick of the load pressure and system pressure equal and excited waveforms are in a critical saturation.When it descends below the critical value, the waveforms tend to symmetries.When it ascends above this point,waveforms tend to square wave.The waveforms under sine wave are basically identical with the waveforms under triangle wave.Waveform distortions follow a linear law with the valve port area,but

the distortions are in a certain range and progressive the border.

根据电液激振系统结构原理，考虑流量与压力之间非线性关系，建立电液激振器数学模型，在典型波形——正弦波和三角波输入条件下，推导其输出振动波形的理论解析式，并对波形进行失真度计算，总结失真规律，最后搭建振动试验装置，采集实际振动波形验证理论分析的正确性。研究结果表明：由于受到弹性负载力方向变化的影响，在典型波形作用下振动波形表现出波峰向外侧、波谷向内侧偏移的斜偏波形，偏斜程度取决于阀口面积的大小；当阀口面积达到某一临界值时，负载压力值刚好达到系统压力值，振动波形处于临界饱和状态；随着阀口面积处于临界值以下并继续减小，振动波形斜偏程度减小，逐渐趋于对称；当阀口面积超过临界值并继续增大时，波形饱和并且饱和程度加深，最后趋于一方波；在正弦波和三角波作用下振动波形基本一致，波形失真度随阀口面积变化呈线性规律，但失真度都在某一确定范围内，并趋近于边界值。

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电液激振器, 振动波形, 失真度, 振动试验