【作者】 董本万；

【导师】 朱建安；

【作者基本信息】 河南理工大学 ， 流体机械及工程， 2009， 硕士

【摘要】 随着煤炭开采科学技术的发展,科研机构对煤芯瓦斯解析测试精度提出了更高的要求,因此研究提钻取芯过程中煤芯瓦斯非等压解析特性是研究者面临的重要课题。研究者希望建立一套提钻取芯模拟系统,在实验室条件下,再现提钻取芯的压力变化过程。由于提钻时间很长,取芯模拟系统实际是一个气体微小流量的精确控制问题。本论文采用数字阀控制模拟系统的压力。电气(液)控制系统由计算机实时控制是今后气动(液压)技术发展的重要趋向,因而研究数字阀系统是当前的一个重要任务。在国内,数字阀系统的发展还不成熟,因此本论文所研究的课题在工业应用中具有重要的理论价值和实际意义。本课题主要研究数字阀对气体微小流量精确控制的控制策略。文中提出的控制策略是模糊控制器控制脉宽调制信号占空比,该策略可以自动地控制数字阀处于开状态的时间,以提高控制精度。通过对脉宽调制技术和模糊控制技术的探讨,建立了相应的数学模型,设计了新型数字阀控制器,并应用数字仿真软件进行数字仿真,研究控制策略对控制结果的影响,为建立试验系统提供依据,在仿真的基础上建立试验系统,进行试验验证。研究结果表明:本论文提出的数字阀控制策略在仿真和试验中都得到了满意的控制效果;在试验中,压力12MPa时,气体的每段平均流量为8ml/min,可以满足提钻取芯模拟系统的压力控制要求。更多还原

【Abstract】 With the development of coal mining science and technology, higher demand is needed for gas decompose test accuracy. To researche the characteristics of the gas non-isobaric analysis from coal core is an important problem for researchers. Pursuer hopes setting up a set of rising drill get core simulation system and reproduction the changed process of pressure in laboratory. Because of getting core need a very long time, the actual stress simulation system is a micro-flow control problem. In this paper the pressure of gas is controlled by micro-flow digital valve. The computer-based real-time control has become an important trend for pneumatic (hydraulic) control system and researching the digital valve system has become an important problem. In China, however the study of digital valve is just underway. Thus the study of this paper is of important theoretical and practical significance.Research the digital valve controller control strategy is the main purpose of this paper. To avoid the control error in entire control process caused by differences, this paper presents a scheme of controlling PWM signal duty cycle with fuzzy controller. The scheme is changing the digital valve at the open status’s time. In order to provide the basis for setting up a test system, we study the PWM technology and fuzzy control technology firstly, design a new type of digital valve controller, set up a mathematical model and finally apply digital simulation software for numerical simulation to study the effects of the control strategy. Based on the simulation, set up a test system, and verified the simulation results. The results shows that the control scheme of digital valve controller in this paper is good, at the simulation and the testing, then can meet the requirement of controlling pneumatic in get core simulation system. The average flux is 8ml/min when the pressure at 12Mpa.更多还原