Ice monitoring of aluminum conductor steel-reinforced cables using guided waves

Abstract

Aluminum conductor steel-reinforced (ACSR) cables are commonly used as power transmission conductors. In cold regions, icing of ACSR cables is a common problem. Ice accretion on ACSR cables may cause various problems. Timely ice monitoring is a primary measure for any type of de-icing solution. In this study, a guided wave-based method was proposed to monitor the ice-forming processes on ACSR cables owing to its advantages of high sensitivity and long-range inspection. The dispersion curves were first obtained using the semi-analytical finite element (SAFE) method for the ACSR cross-section geometry, particularly for different ice thicknesses. They could be used to accurately determine the group velocity for each guided wave mode. Subsequently, a series of tests were conducted with different ice thicknesses in the laboratory. Guided waves were excited by an electromagnetic acoustic transducer (EMAT) in ACSR cables. A new method that combined principal component analysis (PCA) and empirical mode decomposition (EMD) was employed to process the original guided wave signals to obtain effective icing indicator. The results obtained by the guided wave-based method were verified using an image-based method. This study indicates that the proposed ultrasonic guided wave combined with the PCA–EMD method is efficient and sensitive for the ice monitoring of ACSR cables.