Application Prospect of Ultrasonic Testing Methods to Internal Stress in Basin Insulators for GIS

Gas-insulated metal-enclosed switchgear (GIS) is widely used in UHV transmission system and power distribution system in major city, and it has become the preferred equipment for the construction of smart grid. As weakness components of GIS, the uneven distribution of the internal stress of the basin insulator will lead to the whole insulator cracking and even partial discharge, which will affect the safe and stable operation of GIS. Therefore, it is of great significance to study the effective detection method of insulator internal stress for the safe operation of GIS. This paper introduces various ultrasonic internal stress detection methods and their applications from the perspective of ultrasonic type, This paper introduces various ultrasonic internal stress detection methods and their applications from the perspective of ultrasonic type, analyzes the characteristics, limitations and research status of various ultrasonic internal stress detection methods, such as ultrasonic longitudinal wave, transverse wave, combined longitudinal and transverse wave, critical refraction longitudinal wave and Rayleigh wave, and discusses their application prospects in pot insulator.