Composited cable terminals are critical for reliable power delivery of traditional and traction power supply systems. During its operation, the cable terminal continually undergoes complex circumstances where humidity, temperature, field strength, mechanical stress and other factors continuously change at different levels. In extreme cases, defects or even failures may occur in the cable terminals, leading to catastrophic accidents. This makes the condition monitoring and defect detection of composited cable terminals become an imperative need for the power industry. The “state-of-the-art” technology of cable terminal condition assessment is focussed and a systematic review of the current research progress of cable terminal condition assessment from the operation circumstances to failure mechanisms is provided. It covers both online/offline condition monitoring methods and defects detection approaches. In addition, challenges and future research directions for cable terminal condition assessment are also addressed. It is concluded that the non-destructive and non-intrusive methods like terahertz imaging and ultrasonic testing, and multi-source information fusion methods as well as the digital twin technology have been gaining popularity for cable terminal defect inspection. It is expected the presented work can provide a global field of vision for further advancement of both scholars and industrial engineers in this field.

中文翻译：

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复合电缆端子状态监测和缺陷检测方法综述

复合电缆端子对于传统和牵引供电系统的可靠供电至关重要。电缆终端在运行过程中，不断经历湿度、温度、场强、机械应力等因素不断不同程度变化的复杂环境。在极端情况下，电缆终端可能会出现缺陷甚至失效，导致灾难性事故。这使得复合电缆终端的状态监测和缺陷检测成为电力行业的迫切需求。聚焦电缆终端状态评估的“前沿”技术，从运行情况到失效机理，系统回顾了当前电缆终端状态评估的研究进展。它涵盖在线/离线状态监测方法和缺陷检测方法。此外，还讨论了电缆终端状态评估的挑战和未来的研究方向。得出结论，太赫兹成像、超声检测等无损、非侵入方法、多源信息融合方法以及数字孪生技术在电缆终端缺陷检测中越来越受欢迎。预计所提出的工作可以为该领域的学者和工业工程师的进一步发展提供全球视野。得出结论，太赫兹成像、超声检测等无损、非侵入方法、多源信息融合方法以及数字孪生技术在电缆终端缺陷检测中越来越受欢迎。预计所提出的工作可以为该领域的学者和工业工程师的进一步发展提供全球视野。得出结论，太赫兹成像、超声检测等无损、非侵入方法、多源信息融合方法以及数字孪生技术在电缆终端缺陷检测中越来越受欢迎。预计所提出的工作可以为该领域的学者和工业工程师的进一步发展提供全球视野。