Study of Temperature Rise and Discharge Characteristics of Decay-Like Composite Insulator Base on Infrared and Ultraviolet Detection

In recent years, repeated incidents of composite insulator deterioration leading to breakages have posed serious threats to the safety of power systems in China. This study examines a 500kV decay-like composite insulator collected from a field operation, evaluating its outer sheath and core rod degradation status through visual inspection. Infrared and ultraviolet imaging devices were employed to measure the infrared temperature rise and the distribution of ultraviolet discharge under standard operating voltage. The findings indicate that the temperature rise features captured via infrared imaging and the ultraviolet discharge characteristics effectively reflect the deteriorated state of decay-like composite insulators. It was observed that measured temperature rise values decrease with increasing test distance. Additionally, infrared thermography more accurately depicts the internal defects of composite insulators compared to ultraviolet imaging, with reduced interference from surrounding irrelevant discharges.