高压电缆附件铅封缺陷超声检测定量方法  

Quantitative method for ultrasonic testing of lead seal defects in high-voltage cable accessories

作　　者：方春华[1] 周固 饶迪 郭永玉 黄伟丽 别琦涵 Fang Chunhua;Zhou Gu;Rao Di;Guo Yongyu;Huang Weili;Bie Qihan(College of Electricity and New Energy,China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学电气与新能源学院,宜昌443002

出　　处：《电子测量与仪器学报》2024年第6期125-134,共10页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金(51807110);2022年度电网环境保护国家重点实验室开放基金(GYW51202201415)项目资助。

摘　　要：采用相控阵超声技术可以检测高压电缆终端铅封缺陷,为了解决常规的超声定量方法无法有效的检测和定量铅封缺陷的问题,提出了基于超声扇扫图像的高压电缆铅封缺陷定量检测方法,该方法以铅封缺陷纵波扇扫图像为对象并结合了阈值分割和腐蚀算法,能够实时的获取缺陷横截面积、缺陷高度等其他相关信息。首先,搭建了高压电缆终端铅封缺陷超声检测试验平台,对以孔洞、夹渣为代表的不同直径的铅封缺陷进行检测,其次,对采集的铅封超声扇扫图像进行阈值分割和腐蚀算法处理,进行缺陷定量分析,并与传统的-6 dB定量结果进行对比,最后讨论了不同直径缺陷对超声定量结果的影响。研究结果表明,相较于传统的-6 dB法,此方法测量的距离误差缩小了5%,缺陷尺寸精度提高了10%,正确率达到了85%以上,但当铅封缺陷直径增大时,缺陷测量误差也随之升高。该方法验证了采用相控阵超声技术可以高效、直观的检测和定量高压电缆铅封缺陷,为高压电缆铅封缺陷的工程应用提供了重要参考价值,有助于提高高压电缆终端铅封工艺质量,确保电网的运行安全。Phased array ultrasonic technology can be used to detect lead seal defects in high-voltage cable terminals.In order to solve the problem that conventional ultrasonic quantitative methods cannot effectively detect and quantify lead seal defects,this paper proposes a quantitative detection method for lead seal defects in high-voltage cables based on ultrasonic fan-scan images.The method takes the longitudinal wave fan-scan image of the lead seal defect as the object and combines the threshold segmentation and corrosion algorithm to obtain other relevant information such as the cross-sectional area of the defect and the height of the defect in real time.Firstly,an ultrasonic testing platform for lead seal defects of high-voltage cable terminals was built to detect lead seal defects of different diameters represented by holes and slag inclusions.Then,threshold segmentation and corrosion algorithm processing were performed on the collected fan-scan images of lead seal ultrasonic testing,and quantitative analysis of defects was carried out and compared with the traditional-6 dB quantitative results.Finally,the influence of different diameter defects on ultrasonic quantitative results was discussed.The results show that compared with the traditional-6 dB method,the distance error measured by this method is reduced by 5%,the defect size accuracy is improved by 10%,and the accuracy rate is more than 85%.However,when the diameter of the lead seal defect increases,the defect measurement error also increases.This method verifies that the phased array ultrasonic technology can detect and quantify the lead seal defects of high-voltage cables efficiently and intuitively.It provides an important reference value for the engineering application of lead seal defects of high-voltage cables,which is helpful to improve the quality of lead seal process of high-voltage cable terminals and ensure the safety of power grid operation.

关 键 词：电缆终端 铅封 超声 腐蚀算法 阈值分割 缺陷定量 

分 类 号：TN9[电子电信—信息与通信工程] TM75[电气工程—电力系统及自动化]