Current interruption in supercritical fluids

Project Results

It is a bit early to conclude whether supercritical nitrogen will be a suitable switching medium for subsea switches, as more experiments with more product-relevant switch designs will be needed. Nevertheless, SINTEF Energy and NTNU believe that the project has been a success, and the results have contributed to expanding the research frontier on power switches in supercritical nitrogen. The table below summarizes the results obtained during the project period.

Lab Infrastructure

The project has contributed to financing an upgrade of the test infrastructure in SINTEF's safety laboratory (capacitor bank with charging system and power switch, voltage meter, fiber optic system, and control system).

Simulation Model

The project has contributed to the development of a simulation model based on COMSOL that models electrical arcs and how they are influenced by copper in contacts and ignition wire, as well as nitrogen filling pressure and nearby nozzle.

Utility of Results and Plan for Further Exploitation

The project results have primarily led to publications and competence building at SINTEF and NTNU (including the education of master's students, PhD candidates, and postdoctoral researchers), as planned from the beginning. In a research field with very little published material from previous work, NTNU and SINTEF have sought to share the results with other researchers (including R&D environments in industry) to gather input for further research and potential development of new technology. In addition to subsea applications, the project has attracted attention from the medium-voltage DC switchgear community, partly due to the high arc voltage that occurs in high-pressure nitrogen.