Design And Performance Analysis Of The Direct Position Feedback Digital Cartidge Valve

The hydraulic valve is the indispensable unit in hydraulic system. The performance of the hydraulic system is mostly determined by the performance of its valves. With the development of the combination of hydraulic technology, electronic technology and network technology, it would be a trend that all kinds of the valves will be digitized. At the same time, the trend of integration of hydraulic system is developing. So cartridge valves are now more and more dotted by the hydraulic engineers.Based on the main point of the2D servo valve which my lab have owned, this paper come up with an idea that using the outcome of the displacement of the2D valve close-loop control the displacement of the main valve; with the structure of2D servo spiral, the valve output spool displacement in a high accuracy; In order to improve the accuracy of the main valve, this paper choose displacement-flow close-loop control. By MATLAB programming and simulation, it’s easy to set the valve’s parameters and simulate the response rate of the main valve and the2D pilot valve. Finally, the paper verifies the correctness of these new designs. The experiments show that:the above designs can indeed achieve the overall closed-loop. The chapters of the thesis are as follows:In chapter one, at first the development of the electro-hydraulic control technology are reviewed. Then current research situation of domestic and international cartridge valves are introduced. At last, the meaning, purpose and the main tasks of this thesis are given.In chapter two, it details the principle and the structure of2D digital cartridge valve, and processed how to optimize the large stroke digital pilot valve.In chapter three and four, it establishes a mathematical model to describe the procession of the movement of the spool, and simulate in MATTAB to optimize the parameters.In chapter five, it designs all the parameters of the entire valve in detail and checks it. More, it describes the materials and manufacture processes of some key parts.In chapter six, an experiment system is built to analyze the compensation effects of dither signal and the static and dynamic characteristics.In chapter seven, the summarization of this dissertation and the prospect of this research are given.