Interfacial failures and condition monitoring of high-voltage cable accessories: A review

The design and maintenance of cable accessories directly affect the stable operation of cable systems. As the demand for power transmission continues to increase, interfacial discharge and breakdown in cable accessories are among the most common and severe issues in cable systems. Statistical data indicate that cable accessories account for more than 60% of all cable system failures. To improve the detection accuracy and fault prediction capabilities of existing online monitoring technologies for cable accessories, optimizing monitoring methods and exploring new technology applications have become essential. In this paper, a systematic review of the failure mechanisms and condition-monitoring technologies for cable accessories is presented. First, the main causes of cable accessory failures are analyzed in detail, and prior research on interfacial discharge phenomena and breakdown strength is summarized. Second, the technologies currently used for cable accessory condition monitoring are reviewed, including partial discharge monitoring, temperature monitoring, ultrasonic testing, and fiber-optic-based detection technologies. Finally, the limitations of current monitoring technologies are identified, and future development directions for monitoring technologies are discussed. Intelligent monitoring systems that combine artificial intelligence and big data analysis are expected to more effectively assure the reliability and safety of cable accessories in the future.