电液激振器, 振动波形, 失真度, 振动试验

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.