Abstract
The frequency bandwidth of the conventional electro-hydraulic vibration exciter is highly dependent on the servo valve's response speed, which is always limited to a rather narrow range. A novel scheme of electro-hydraulic vibration exciter using a two-dimensional valve (2D valve) to control a hydraulic actuator is proposed in order to extend the frequency range. In this 2D valve, the rotary and linear motions of a spool are controlled independently to produce the reciprocating motion of the piston of the cylinder. The frequency and the amplitude of the excited waveform are separately controlled by the rotary motion and the sliding motion of the spool respectively. The frequency is related to the rotary speed of the spool and the coupling pattern between the grooves on the spool and windows on the sleeve. This configuration could easily extend the frequency of the hydraulic vibration exciter by increasing the rotary speed of the spool and the number of the grooves on the spool area. Based on the work principle of the electro-hydraulic vibration system, the mathematical models are first established considering a nonlinear relation between pressure and flow. Then the analytic solution to excited waveforms is solved using the subsection integration method. And the expression equations of correlated parameters are given. Finally, real excited waveforms are obtained to validate the theoretical analysis result. The results reveal that the load of electro-hydraulic vibration exciter using a 2D valve is mainly the elastic force in low frequency section, so the ascent and descent slopes of excited waveform demonstrated somewhat asymmetrically in respect that the direction of the elastic load is changed. The extent of asymmetry depends on the 2D valve's axial opening. When it exceeds a critical value, the excited waveform tends to the saturated state because of pressure saturation. The exciter waveform is also influenced by hydraulic resonance as the input frequency approaches the hydraulic resonant frequency.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
