Electrical Characterisation of Solid-Liquid Composite Insulation Systems used in Subsea Connectors

海底电力输送不仅对石油和天然气开采至关重要，而且对开发海上可再生技术也至关重要。高压电缆连接器通常需要在海底环境中配合/脱离。矿物油已被用作海底电缆连接器中的介电液体。然而，在意外泄漏的情况下，它会造成污染海水的风险。因此，有动机使用具有低环境影响的替代介电液体。合成酯是这样一个替代的候选人，由于其优越的上级生物降解性。此外，合成酯由于其高燃点/闪点，可以提供更好的消防安全保障，约为矿物油的两倍。该博士课程旨在研究电缆连接器绝缘材料的电气特性，包括硅树脂-PEEK-酯在体绝缘和沿固液界面沿着爬电放电/表面跟踪现象的击穿强度方面。该项目将从深入的文献综述开始，然后设计合适的实验装置。固体绝缘材料的击穿强度将在不同温度下进行测试。研究了沿着固液界面的爬电放电和沿面跟踪，从起始、发展到击穿的各个阶段。将考虑短期和长期应力。该研究将促进更绿色、更安全的海底高压电缆连接器的应用。

Subsea power delivery is essential for not only oil and gas recovery but also for developing off-shore renewable technologies. High voltage cable connectors are often required to mate/demate at the subsea environment. Mineral oil has been used as the dielectric liquid in the subsea cable connectors. It, however, poses a risk to contaminate the sea water in case of unexpected leakage. Therefore, it is motivated to use alternative dielectric liquids with low environmental impact. Synthetic ester is such an alternative candidate due to its much superior biodegradability. In addition, the synthetic ester can provide better fire safety guarantee due to its high fire/flash point, which is about double of that of mineral oils. This PhD programme aims to investigate the electrical characteristics of the cable connector insulation materials including Silicone-PEEK-Ester in terms of breakdown strength of the bulk insulation and creepage discharge/surface tracking phenomena along the solid-liquid interface. The project will start from an in-depth literature review and then followed by designing the suitable experimental setup. Breakdown strength of the solid insulation materials will be tested at different temperatures. Creepage discharge and surface tracking along the solid-liquid interface will be studied from initiation, propagation and till breakdown stages. Both short-term and long-term stresses will be considered. The study will promote applications of greener and safer subsea high voltage cable connector.