【作者】 王国锋；

【导师】 李长春；

【作者基本信息】 北京交通大学 ， 检测技术与自动化装置， 2008， 硕士

【摘要】 本文以接触网零部件疲劳试验机为研究对象,利用数字控制的优势和现代控制理论的有关成果,旨在改进原来的模拟系统。根据疲劳试验机的固有特点,提出针对性的数字控制算法,同时研制出原理样机,使其能根据需求,完成满足一定规律的可控试验过程。首先,作者在阅读了大量的国内外资料的基础上,概述了国内外公司在疲劳试验机控制器方面的研究成果,并根据我们的项目需求,提出了本论文要解决的问题。文章在分析了试验机工况的基础上,研究了阀控非对称液压缸位置系统和力控系统的数学模型,进一步分析了液压缸的非对称性所引起的系统静差,并将系统数学模型离散化,得到了便于应用数字控制的离散化数学模型,在此基础上对位置系统和力控系统数学模型进行了仿真计算,确定了合理的控制策略。设计了数字PID控制器对位置闭环和力控系统进行校正,并在此基础上采用动压反馈来提高系统性能,试验结果证明采用动压反馈能有效地提高系统的阻尼比。针对试验机的需求分析,提出了控制系统的硬件实施方案。选择ARM系列芯片中的AT91RM9200作为控制器的CPU,采用S1D13506的LCD控制器来完成图形用户界面的设计,根据信号采集的需要,选择16位的AD7825和DA7644芯片来完成数据的模拟量输入输出功能。在硬件平台基础上,选择Linux作为控制器的操作系统,完成了Uboot和Linux操作系统内核的配置和移植,编写了控制器的A/D、D/A、LCD等多个功能模块驱动程序;针对Linux在实时性方面的不足,采用了Xenomai技术弥补了Linux在实时性方面的不足;移植了MiniGUI软件,实现了控制器的人机接口功能,并运用MiniGUI开发了疲劳试验机的控制应用程序。最后,作者在某疲劳实验机上进行了实验研究,检验了控制算法与控制器的有效性与可行性,证明了硬件选型、设计以及软件编程的正确性,达到了预期的控制效果。更多还原

【Abstract】 In order to improve the performance of original analog controller, this paper studied fatigue testing machine for catenary, thanks to the advantage of digital control and the development of modern control theory. According to the characteristic of fatigue testing machine, the digital control algorithm was presented and implemented in an example testing machine. Due to user’s requirements, the digital controller had accomplished controllable processes followed given rules.The research achievement on application of the digital controller of fatigue testing Machine at home and abroad was roughly described by a lot of documents, and according to the needs of the project, the main subjects are drafted.This paper presented the work conditions of the testing machine. It was studied that the plant model of position and force system about valve control unsymmetrical hydraulic ram. Then it was analyzed that static error was caused by unsymmetrical hydraulic ram. For digital control application, the continue model was transformed to discrete one. Then, simulations about position and force system were done for choosing right control strategy. A digital PID controller was designed to the closed-loop system. And on this basis, using dynamic pressure feedback to improve system performance, the results proved that dynamic pressure feedback could perfectly improve the damper.According to the needs of testing machine, the paper discussed a hardware architecture of control system which was based on AT91RM9200(ARM) as controller’s CPU, S1D13506 as LCD controller to realize the graphical user interface, and 16-bit AD7825, DA7644 to complete the Analog input and output data conversion in view of the need of signal acquisition.Based on the hardware platform, the transplant of the embedded software platform of U-boot and Linux Operating were investigated. The drivers and application software of several interfaces, including the A/D and D/A converter、LCD module were programmed. Because Linux is not real-time system, Xenomai module had been used by embedded linux system to realize the real-time processing function, The transplant of MiniGUI software ensured the smooth development in system graphics user interface. On the basis of the above , The application of Fatigue testing machine control system is developed by MiniGUI.Finally, author implemented the control algorithm in a digital controller for fatigue testing machine system. Control algorithms and digital controller were proven to be available and realizable. The choices of hardware and design of software were also proven to be validity. The controller achieved all expectable results.更多还原