Abstract:
Inspection of Overhead Transmission Line (OVTL) cables is regularly performed using various Non-Destructive Testing (NDT) techniques, such as on-ground and airborne visual inspection; however those techniques have limitations and safety concerns. In this study, ultrasonic guided waves (UGW) for structural integrity analysis is investigated. Aluminium Conductor Steel Reinforced (ACSR) cable specimens are interrogated using shear mode Lead Zirconium Titanate (PZT) transducer array in through transmission and pulse-echo configurations. Identification and analysis of wave propagation for a broad range of frequencies is followed by the effect of defect location and depth on wave propagation. Wavelet denoising technique is then investigated for inspection quality improvement. Preliminary results yield successful detection of defects on a 26-metre long ACSR cable and considerable Signal-to-Noise Ratio (SNR) improvement.
