ISBN 9783843954044

978-3-8439-5404-4, Reihe Energietechnik

Frederik Anspach
Experimental Research and Modelling of LVDC Hybrid Switch Recovery Voltages

215 Seiten, Dissertation Technische Universität Braunschweig (2023), Softcover, A5

Zusammenfassung / Abstract

The efficient transmission of large amounts of energy is one of the challenges in electrical power engineering. DC grids are a key technology. In mobile and HVDC transmission systems, they are already state of the art, but the application at stationary low and medium voltage levels is still the subject of research projects. In addition to the grid itself, the requirements on the components, e.g. switching devices, are also increasing. Optimisation of the switching devices alone is no longer sufficient; system interoperability, in the form of "intelligence", must also be increased simultaneously.

A investigation of the recovery voltage of LV HCBs forms the basis for understanding the deionisation process. Due to the wide range of requirements, the systems engineering method is used for the investigation. After a literature research, which is equivalent to the requirements analysis, the concept definition of the recovery voltage model is carried out. The focus is on the modularity of the approach and ensuring physical validation. In the subsequent system definition, the boundary conditions of the model are determined, these are transferred to the simplified mathematical description and the measurement technology to be used is defined. The following verification is subdivided into the evaluation of the multiphysical measurement results for electrics, optics and pressure. These results are used in the model sensitivity analysis and parameterisation. The following validation of the developed model, with a focus on accuracy and connectivity to the overall DC system, concludes the method.

Based on this work, three core tasks can be derived for future research: First, continuation of the multiphysical measurement method to optimise the understanding of the plasma recovery process. Second, extension of the model description from the approximated model setup to a real hybrid switch. Thirdly, application of the developed method to other components of the DC system.