涡流检测高压电缆附件铅封缺陷的试验研究

为了可靠检测高压电缆铅封状态,解决人工铅封检查效率低下电缆附件故障高的问题,提出高压电缆附件铅封缺陷涡流检测方法。通过分析高压电缆附件铅封常见结构、缺陷,根据涡流检测原理与特点,提出铅封涡流检测的影响因素及适用理论。获取铅封试样制作铅封模拟缺陷,调试铅封涡流检测专用探头、仪器参数,采集、评价有缺陷和无缺陷位置涡流图谱并实施应用试验,验证了依靠常用涡流检测设备检测高压电缆附件铅封表面开裂缺陷的可行性。证明了不拆除外部绝缘条件下的高压电缆附件铅封涡流检测可靠性,铅封试样的涡流检测具有不受检测位置影响、检测速度快、检测精度高的优势。试验研究结果为完善高压电缆附件铅封涡流检测工艺,开展高压电缆铅封接头故障检测提供了有效技术参考。

Experimental Study on Eddy Current Testing of Lead SealingDefects in High Voltage Cable Accessories

In order to detect lead sealing status of high-voltage cable reliably and solve the problem of low efficiency of manual inspection of lead sealing and high fault of cable accessories,the eddy current testing method for lead sealing defect of high-voltage cable accessories is proposed.Based on the analysis of the common structure and defects of lead sealing of high-voltage cable accessories,influence factors and applicable theories to the eddy current test of the lead sealing are put forward according to the principle and characteristics of the eddy current test.Lead sealing samples are obtained to make simulated defects.The special probe and instrument parameters for the lead sealing eddy current test are debugged.The eddy current signal spectrums of the defect and defect-free location are both collected and evaluated,and the test application is carried out.The feasibility of using the common eddy current equipment to detect cracking defects located on the surface of lead sealing in high-voltage cable accessories is verified.It is proved that the eddy current testing of high-voltage cable accessories under the condition of external insulation is reliable.The eddy current testing of lead sealing samples has the advantages of not being affected by the test location,fast detection speed and high detection accuracy.The experimental results provide an effective technical reference for improving the eddy current testing process parameters of high-voltage cable accessories and fault detection of high-voltage cable lead sealing joints.