Research on corrosion detection of ultrasonic guided wave transmission tower wire pulling device based on SVD-OMP

To achieve rapid and efficient corrosion detection of the stay wire devices in transmission towers, this paper proposes an ultrasonic guided wave detection method based on a SVD-OMP (Singular Value Decomposition - Orthogonal Matching Pursuit) joint algorithm to address the ultrasonic guided wave signal aliasing issue in the complex structures of stay wire devices. Through numerical analysis, suitable ultrasonic guided wave modes and detection frequencies for stay wire device inspection are determined. A simulation model of the stay wire device with corrosion defects is established. The propagation characteristics of the L(0,2) mode guided waves in the stay wire device are analyzed using finite element simulation. The SVD algorithm is employed to separate primary and secondary components of aliased signals, while the OMP algorithm is combined to sparse-reconstruct secondary component signals, successfully extracting corrosion defect echoes. Research results show that the time delay difference in reconstructed signals deviates from the theoretical acoustic path by less than 6.36 μs. The corrosion depth exhibits a positive correlation with echo amplitude, which tends to saturate when the radius exceeds 7 mm. The study verifies the effectiveness of the SVD-OMP algorithm in detecting defects within the complex structures of stay wire devices, providing a novel approach for corrosion detection in transmission tower stay wire devices.