Research On 2D Digital Relief Valve With Electrical Feedback

Relief valve is an important pressure control component in hydraulic drive system. Its main functions are: regulating and stabilizing the hydraulic system maximum pressure, spilling the extra oil; preventing overload, and ensuring the pressure safety. In order to improve the steady-state accuracy and dynamic stability of relief valve, the structure of relief valve was improved on the one hand and the hydraulic control method was innovated on the other hand.A new 2D digital relief valve was adopted in this thesis. The functions as guide valve and main valve were realized by two degree of freedom that is spool rotation and linear displacement of valve core which greatly simplify the structure of relief valve. The given pressure of system was detected directly by pressure sensors. The performance of 2D digital relief valve was improved through pressure closed-loop control which can achieve long-distance monitoring and automatic adjustment. Mathematical model of electrical feedback 2D digital relief valve was established in this thesis, and numerical simulation was carried out based on theoretical model, at last the experiment was finished to test the performance electric feedback 2D digital relief valve. Experimental results showed that the performance electric feedback 2D digital relief valve is well. The contents of each Chapter are listed as follows:Development of hydraulic technology and electro hydraulic digital control technology were introduced in chapter 1, and the research and development trends of relief valve were also introduced in this chapter. The background, meaning and the task need to be done is introduced too.Theoretical model of electrical feedback 2D digital relief valve was established in chapter 2, and this model was simulated and analyzed applied numerical solution method.Composition and design of electric feedback 2D digital relief valve was introduced in chapter 3 including hardware and software design of signal acquisition control board.Experiment of electric feedback 2D digital relief valve was carried out in chapter 4 including open-loop, closed-loop experiments. And the performance was also analyzed.The results are summarized and the prospects of this thesis are proposed in chapter 5.