The Optimal Design And Experimental Study Of 2D High-frequency Excitation Valve

With the development of modern industrial,especially aerospace technology, the higher requirement of vibration frequency, output and controllability are put forward to electro-hydraulic vibration exciter. Its performance quality and technical level directly impact on the technological progress and development of industrial engineering.As the key components of electro-hydraulic vibration exciter, 2D high-frequency excitation valve and it's the control method have been optimized to further improve electro-hydraulic vibration exciter performance. It solves the problems of the original 2D valve, such as complex structure, poor controllability, vibration frequency is still limited and difficult to adjust the zero position. The theoretical and experimental study results are clarified that the new structure of electro-hydraulic vibration exciter controlled by a 2D valve is simpler, its control accuracy is higher, and the excited frequency is above 3000HZ。The main work and achievements are as follows:1. The structure of 2D high-frequency excitation valve is greatly optimized, reducing the processing and installation difficulty. By increasing the number of the grooves of the 2D valve spool and the windows of the 2D valve sleeve to 16, the vibration frequency is improved. Designing a link structure of the hybrid linear step motor fixed with plug instead of eccentric wheel mechanism to control the axial displacement of 2D valve spool and vibration amplitude, and using AC servo motor connected with high-speed gear box transmission structure instead of hydraulic motor to control rotary speed of 2D valve and vibration frequency, excitation exciter controllability and the control precision are enhanced. In the hybrid linear step motor bracket we design an adjustment screw and lock nut to adjust the zero position of 2D valve.2. On the basis of analysis the working principle of the electro-hydraulic vibration exciter controlled by a 2D valve, the mathematical model and transfer function is established through four way valve flow equation, hydraulic cylinder flow continuity equation, force balance equation between hydraulic cylinder and load.3. The ideal and work flow characteristics of the 2D high-frequency excitation valve are both analyzed and simulated. It is also focus on the study of displacement solution and simulation when the valve orifice area is changed. The spectrum and distortion analysis is used to analysis saturated and unsaturated phenomenon under different spool opening.4. The fourth-order Runge-Kutta method is used to solve hydraulic cylinder piston displacement, load pressure and other parameters in Matlab. Simulation analysis of high-frequency is also been done.5. The experiment platform and testing system based on electro-hydraulic vibration exciter controlled by a 2D valve are established to collect actual excitation waveforms and the two cavities of the hydraulic cylinder pressure waveforms. At last, the actual excitation waveforms are analyzed, compared and studied.