Analysis of Defect Detection for 10 kV Composite Insulator Based on the Microwave Method

During the long-term operation of composite insulators in transmission lines, they are easily affected by harsh environments, resulting in hidden defects such as surface contamination, shed damage, and adhesive failure. A defect detection method based on microwave for composite insulators was proposed, and a corresponding numerical simulation model was established. A large-aperture horn antenna model with a wide frequency band and high gain was built, the accuracy of which was verified. In the simulation, shed crack defects were selected as representative probes to model typical defects in the sheds, sheath, and core rod of composite insulators. This study investigated defects with varying severity levels and spatial distributions while also exploring optimal placement configurations for detection antennas. An experimental platform was built for testing, and it was found that the experimental results showed a similar changing trend to the simulation results, which further verified the accuracy of the simulation model and the feasibility of simulating defects.