基于功率谱估计的管道腐蚀超声波内检测数据压缩研究

Ultrasonic in-line Inspection Data Compression Study of Pipeline Corrosion based on Power Spectrum Estimation

在管道内内独立运行的管道超声波内检测器扫描管壁腐蚀情况时,将面临海量数据存储问题。本文通过大量实验和理论研究,提出利用管道壁厚的测量范围,存储一定频率范围的功率谱,实现A扫描数据压缩。该方法在提高数据压缩比(如100M采样率时压缩比达到11.8%,50M压缩比达到23.6%)的同时,压缩信号还原后与原始信号的近似相关度仍然能保持97%左右,且计算简单,运算速度快,还原信号清晰可实现在线压缩,符合工程的要求。

When Pipeline Inner Inspection Tool scans the pipe wail corrosion independently, it will face mass data storage problem. In this paper, a large number of experiments and theoretical studies are made to solve this problem, we put forward a method by storing particular range of frequency spectrum basing on pipe wall thickness measurement range, to achieve A-scan data compression. The method not only improved the data compression ratio （compression ratio reaches 11.8% at the sample rate of 100M, compression ratio to 23.6% at the rate of 50M）, but also the approximate correlation rate of original signal and recovered signal is still maintained at the level about 97%, and the calculation is simple the operation is fast, the restored signal is clear and vivid, meets the engineering requirements.