Affiliation:
1. High Magnetic Group, Songshan Lake Mat Lab, Dongguan, China
2. Baisha Power Supply Bureau, Hainan Power Grid Corporation, Haikou, China
Abstract
In the construction of overhead distribution network lines, ensuring the stability and construction quality of utility pole foundations is crucial. Traditionally, this process may involve excavation and direct inspection, which is not only time-consuming but may also cause environmental damage. The non-destructive detection scheme proposed in this paper, based on the transient electromagnetic method (TEM), offers an efficient and non-intrusive method for detecting the burial conditions of utility pole bases, pulls, and chucks. The transient electromagnetic method is a geophysical exploration technique that uses the principle of electromagnetic induction to detect the distribution of underground materials. When detecting utility pole bases, this method analyzes the electromagnetic response generated by underground metallic structures to obtain information. However, traditional TEM has a blind zone problem in shallow metal detection, which limits its application in utility pole base inspection. To address this issue, the scheme proposed in this paper introduces a decoupling coil to eliminate interference caused by the primary magnetic field. This decoupling technology significantly improves the detection discrimination, allowing for a more accurate determination of the burial depth and condition of bases, pulls, and chucks. Finite element numerical analysis using COMSOL 5.4 is adopted to examine the underground magnetic field distribution and optimize coil parameters. This analysis helps to understand the interaction between the electromagnetic field and underground structures, guiding the design of coils and the development of detection strategies. The prototype experimental platform built further validates the effectiveness of the scheme. Experimental results include measured data of magnetic field variations, assessments of detection depth and resolution. These experimental results are crucial for verifying the practical application potential of the non-destructive detection scheme.