Composite dielectric structures with enhanced lifetimes

多年来，我们的输配电网络背后的工程技术一直保持不变。其中一个原因是，在我们的铁路基础设施中发现的电气绝缘系统的可靠性已被证明是非常高的。然而，许多现有的基础设施现在已经非常陈旧，远远超过了其设计寿命。此外，电力系统目前正在实施根本性的变革。这在很大程度上是由促进可再生（低碳）能源供应的愿望推动的。此外，随着电力取代天然气为家庭供暖，电动汽车取代汽油和柴油动力汽车，更多的电力将被消耗，需要更大的电力传输密度，特别是进入我们的城市。这些要求需要更高的绝缘电气应力和更高的额定温度，同时保持可靠性。由于这些原因，提高我们对绝缘失效机制的理解和设计改进的绝缘对我们电力系统的进一步发展都是至关重要的。绝缘系统的可靠性在发电、铁路网和制造业中也至关重要。这个项目将提高我们对绝缘可靠性的理解，并开发性能更好的结构材料。特别是一个基本的老化机制，在聚合物绝缘称为电气树将详细研究。电树生长是聚合物绝缘系统在高电应力下长期失效的一种机制，是一个导致类似植物树的人工制品发展的过程。它由直径达几十微米的管状空心树枝组成。树的存在最终导致绝缘失效。该项目将考虑如何使用分层电介质来提高绝缘寿命，特别是在电气树存在的情况下。Rowland教授（曼彻斯特大学）和Choy教授（伦敦大学学院）最近进行的可行性研究表明，薄层聚合物可以将树木的繁殖时间改变一个数量级。此外，曼彻斯特的新技术现在已经能够生成树木生长过程的三维图像。这使用了伦敦大学学院独特的实验设备和样品制备技术，以及曼彻斯特大学的成像能力，包括钻石光源x射线设备。虽然这项工作是基于基础科学，但该项目的一个关键组成部分将是利用这些发现并开发一个改进分层电介质结构的框架。将为电网、公共交通和电力电子工业的工艺和产品的未来发展制定路线。已获得外部伙伴对制定这一框架的承诺，以确保在项目生命周期内进行技术转让。最终，这项工作将有助于实现更好的性能、更低的成本和更强大的电力供应。

For many years the engineering behind our power transmission and distribution networks has remained unchanged. One reason for this is that the reliability of electrical insulation systems, also found on our rail infrastructure, has proved extremely high. However much of the existing infrastructure is now very old, well beyond its design life. In addition, radical changes are now being implemented in power systems. These are largely driven by the desire to facilitate renewable (low carbon) energy supplies. Moreover as electricity replaces gas for heating homes, and electric vehicles replace petrol and diesel powered cars, more electricity will be consumed requiring greater densities of power transmission, particularly into our cities. These requirements necessitate higher electrical stresses on insulation and higher temperature ratings, whilst maintaining reliability. For these reasons improving our understanding of the failure mechanisms of insulation and designing improved insulation are both critical to the further development of our power systems. Reliability of insulation systems is also critical in power generation, rail networks and manufacturing industries.This project will improve our understanding of insulation reliability and develop structured materials with improved performance. In particular a fundamental ageing mechanism in polymeric insulation known as electrical treeing will be studied in detail. Electrical tree growth is a mechanism of long-term failure in polymer insulation systems under high electrical stress and is a process leading to the development of an artefact which resembles a botanical tree. It consists of tubular hollow branches of up to tens of microns in diameter. The presence of a tree eventually leads to insulation failure. The project will consider how the use of layered dielectrics can enhance insulation life, particularly in the presence of electrical trees. Recent feasibility work between Prof Rowland (University of Manchester) and Prof Choy (UCL) has shown that thin layers of polymers can change tree propagation times by an order of magnitude. Also novel techniques in Manchester have now enabled three-dimensional imaging of the treeing process to be generated. This has used unique experimental facilities and skills for sample preparation at UCL and the imaging capability at the University of Manchester including the Diamond Light Source X-ray facility. Although this work is based on fundamental science, a key component of the project will be take the findings and develop a framework for improved layered dielectric structures. A route for future development of processes and products for the power networks, mass transit and power electronics industries will be developed. The commitment of external partners to generating this framework has been obtained to ensure technology transfer during the project life. Ultimately this work will contribute to better performing, lower cost and more robust electricity supplies.