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Streamer Propagation Along Liquid/Solid (fibre) Interfaces

Project Name: Physics of the dielectric failure mechanism of new materials engineered for liquid and liquid/solid insulation systems

About the project

Nowadays, the existing electrical power grid needs to be upgraded to the next-generation system, known as the smart grid. This implies a fundamental need for re-engineering of the Power System Components in order to satisfy the demand of the future grid. Due to the advances on Material Science, today is possible to design novel materials with radically improved properties opening new opportunities to develop and improve the Power System Components with superior characteristics.

Even though standard breakdown voltage tests are commonly used to characterize the performance of these new materials in electrical insulation systems, more sensitive experimental techniques are required. This PhD project is aimed to investigate the fundamental physical processes of the electrical failure of non-conventional materials at liquid and liquid/solid interfaces (e.g transformer oil-pressboards).

Project description

The PhD project is aimed to investigate the fundamental physical processes of streamer initiation and propagation, related to the dielectric failure of liquid and liquid/solid insulating systems, based on non-conventional materials (e.g. oil with nanoparticles, biodegradable oils, engineered cellulose and polymers, etc). The project aims to gather basic physical experimental data on the streamer inception propagation in non-conventional insulating materials. It also includes the identification, analysis and characterization of the main physical and chemical material properties that influence the process of insulation failure. Furthermore, it includes the development of macroscopic simulation models to improve the interpretation of experimental results and to predict the insulation performance of the new materials under the conditions typical in power components.

Experimental setup to investigate streamers in liquids and in liquid/solid interfaces
Example of a shadowgraph of negative streamer propagating in mineral oil
Example of shadowgraph set showing a) The needle configuration close to the mineral oil/pressboard interface, b) A streamer propagating along the mineral oil/pressboard interface, c) detail of the streamer propagating along the oil/pressboard interface.