【作者】 郝勇娜；

【导师】 梁鸿生；

【作者基本信息】 西安理工大学 ， 检测技术及自动化装置， 2004， 硕士

【摘要】 电涡流传感器检测技术是近年来应用较广泛的一种无损检测方法，它同磁粉检测、超声波检测、射线检测和渗透检测统称为五大无损检测技术。论文中，首先介绍了电涡流检测技术的现状、应用范围及发展方向，接着阐述了电涡流传感技术在课题中的应用。 深刻理解涡流检测的基本原理，是选择涡流检测方案的理论依据。论文第二章从多个角度分析了电涡流检测的原理，在对电涡流检测等效电路分析的基础上，提出了电涡流检测技术在铝箔厚度在线检测系统中应用的可行性，文中还详细讨论了电涡流传感器的设计方法及课题中电涡流传感器参数地选择。 硬件电路是系统设计的基础，也是整个检测系统功能实现的关键。论文第三章结合铝箔生产现场的实际情况，选取TI公司的DSP微处理器芯片构成硬件电路的微处理系统处理检测到的信号。硬件电路的设计主要分三大部分来实现：激励源电路部分，由分频电路和频率合成电路组成，产生频率稳定的激励信号以确保检测任务的正常进行；传感器变换电路部分，由放大电路、滤波电路、检波电路、鉴相电路和数据采集电路组成，主要将电涡流传感器检测线圈检测到的信号变换成只含有被测信息的离散信号，易于后续电路处理；由DSP芯片构成的微处理系统，主要完成检测系统的数据拟合、显示及与主机通信等功能。本章最后部分介绍了硬件设计过程中常见的干扰问题及课题中采取的消除干扰的措施。 测控系统的硬件电路确定之后，测控系统的主要功能将依赖于软件来实现。论文第四章介绍了课题的软件设计思路以及设计过程中的系统自检、容错处理、软件抗干扰等问题。 检测过程中不可避免地存在着测量误差，除了从硬件方面考虑减少或消除误差采取的措施外，论文第五章从数据拟合方面详细介绍了减少拟合误差的方法——免疫算法，并将数据拟会结果‘SB－P算法对数据的拟合结果进行比较。证明了免疫算法对数据拟合具有较高的精度。最后一章通过对系统总体误差的分析，结果论证了课题中检测系统设计方案的可行性。更多还原

【Abstract】 Eddy-current sensor test technology is a kind of very popular untouched nondestructive test technology developed in last decades, which makes up five major modern nondestructive test technologies together with magnetic particle test, radial test, ultrasonic test and osmosis test. The nowadays of eddy-current test technology, the application field of eddy-current test technology and the development direction of eddy-current test technology are present in this paper.Understanding the basic theory of eddy-current test is the basis of selecting eddy-current test plan. In chapter 2, eddy-current test theory is analyzed from several aspects. Though analyzed the equivalent circuit of eddy-current test, the reliability of eddy-current test technology on aluminum foil thickness test on line is given and the eddy-current sensor design method and the eddy-current sensor parameters selecting are discussed.Hardware design is the basis of the whole system and the other system designs must be made on the basis of it. Together with the facts in chapter 3, the hardware microprocessor system that made by DSP chip of TI corporation is used to process the sample signal. Hardware circuit design is divided three parts. Generated frequency circuit includes frequency divided circuit and frequency composed circuit to generate stable frequency signal to sure the test task. Eddy-current sensor conversion circuit consist amplification circuit, band-pass filter circuit, demodulation circuit, differentiation phase and data sampling circuit. These circuits are used to convert the test signal of eddy-current sensor to discrete signal tend to process. The microprocessor system that formed of DSP chip is used to data fitting of test system, data displaying and data communicating with personal computer, etc. The interference questions of hardware design and the measure ofeliminating interference signal in the subject are introduced in the last of this chapter.After the hardware circuit of test system is conformed, the function of test system is relayed on the software. The software design ideas of the subject, system automatic test during the design, system consistent error disposal and software anti-interference questions are recommended in chapter 4.There have not avoided test errors in the test process. Except the hardware measures are taken to eliminate the errors, the methods of eliminating errors from data fitting aspect are introduced in detail in chapter 5, that is immune algorithm. The results have testified to get higher precision using immune algorithm to process sampling data compare with using B-P algorithm. Though analyzed the whole error of the test system, the results proved feasibility of the design plan of test system.更多还原