基于LabVIEW和小波分析的高精度X射线测厚系统实现

发布时间：2019-03-03 09:28

【摘要】：在金属板材生产中,测厚系统的测量精度直接影响板材产品的质量。为了满足汽车、船舶、房地产等高端领域对金属板材高质量的要求,精度高、响应快的在线测厚系统的研究显得十分重要。在线测厚系统在金属板材生产过程中主要作用是实现产品厚度的在线测量及监控,以达到板材产品测厚高精度的要求。本课题研发了一套应用于中小型冷轧现场的高精度X射线在线测厚系统。为了提高系统的测量精度,文中从改善X射线电源性能、厚度数据去噪算法和系统抗电磁干扰能力三个方面做出详细设计。⑴X射线电源设计采用全桥移相控制软开关技术,并使用了集成稳压与双向倍压整流两个模块,提升了输出电压且减少输出纹波。⑵系统利用MATLAB小波工具箱引入小波分析对厚度数据去噪处理,提高数据精度,充分发挥MATLAB在工程运用中的优势。⑶针对工业现场的电磁干扰,系统从软硬件两个方面进行加固,提高了系统稳定性,保证测量精度。系统设计中采用虚拟仪器-LabVIEW搭建的上位机实现了厚度数据及波形在线显示、历史数据存储与查询等功能,并设有超值报警系统。下位机采样控制系统则采用DSP2812控制器,实现对X射线电源的控制和厚度数据的采样。本系统完成了样机的设计及测试,提高了X射线测厚系统对金属板材厚度测量精度,满足了冷轧现场对板材厚度的测量要求。
[Abstract]:In the sheet metal production, the measuring precision of the thickness measuring system directly affects the quality of the sheet product. In order to meet the high-end field of automobile, ship, real estate and so on, the research of on-line thickness measurement system, which has high quality, high precision and quick response, is very important. The main function of on-line thickness measurement system in the process of sheet metal production is to realize on-line measurement and monitoring of product thickness in order to meet the requirements of high accuracy of thickness measurement of sheet metal products. In this paper, a high precision X-ray on-line thickness measurement system is developed for small and medium-sized cold rolling site. In order to improve the measurement accuracy of the system, a detailed design is made from the aspects of improving the performance of X-ray power supply, the denoising algorithm of thickness data and the anti-electromagnetic interference capability of the system. 1the full-bridge phase-shift control soft-switching technology is used in the design of X-ray power supply. The two modules of integrated voltage stabilization and bi-directional voltage doubling rectifier are used to improve the output voltage and reduce the output ripple. 2 the system uses MATLAB wavelet toolbox to introduce wavelet analysis to de-noising the thickness data and improve the data precision. The advantages of MATLAB in engineering application are brought into full play. 3 in view of electromagnetic interference in industrial field, the system is strengthened from two aspects of hardware and software, which improves the stability of the system and ensures the precision of measurement. In the design of the system, a virtual instrument-LabVIEW is used to realize the functions of on-line display of thickness data and waveform, storage and query of historical data, and a super-value alarm system. The sampling control system of the lower computer adopts DSP2812 controller to realize the control of X-ray power supply and the sampling of thickness data. This system has completed the design and test of the prototype, improved the precision of measuring the thickness of sheet metal by the X-ray thickness measuring system, and satisfied the requirement of measuring the thickness of the sheet in cold rolling field.
【学位授予单位】：安徽工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG335.5;TG115.281

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