Universität zu Köln

Kaiser, Franz Nikolas ORCID: 0000-0002-7089-2249 (2022). Resilience of power grids and other supply networks: structural stability, cascading failures and optimal topologies. PhD thesis, Universität zu Köln.

Preview

PDF PhD_Thesis_Franz_Kaiser.pdf - Published Version Download (27MB) | Preview

Abstract

The consequences of the climate crisis are already present and can be expected to become more severe in the future. To mitigate long-term consequences, a major part of the world's countries has committed to limit the temperature rise via the Paris Agreement in the year 2015. To achieve this goal, the energy production needs to decarbonise, which results in fundamental changes in many societal aspects. In particular, the electrical power production is shifting from fossil fuels to renewable energy sources to limit greenhouse gas emissions. The electrical power transmission grid plays a crucial role in this transformation. Notably, the storage and long-distance transport of electrical power becomes increasingly important, since variable renewable energy sources (VRES) are subjected to external factors such as weather conditions and their power production is therefore regionally and temporally diverse. As a result, the transmission grid experiences higher loadings and bottlenecks appear. In a highly-loaded grid, a single transmission line or generator outage can trigger overloads on other components via flow rerouting. These may in turn trigger additional rerouting and overloads, until, finally, parts of the grid become disconnected. Such cascading failures can result in large-scale power blackouts, which bear enormous risks, as almost all infrastructures and economic activities depend on a reliable supply of electric power. Thus, it is essential to understand how networks react to local failures, how flow is rerouted after failures and how cascades emerge and spread in different power transmission grids to ensure a stable power grid operation. In this thesis, I examine how the network topology shapes the resilience of power grids and other supply networks. First, I analyse how flow is rerouted after the failure of a single or a few links and derive mathematically rigorous results on the decay of flow changes with different network-based distance measures. Furthermore, I demonstrate that the impact of single link failures follows a universal statistics throughout different topologies and introduce a stochastic model for cascading failures that incorporates crucial aspects of flow redistribution. Based on this improved understanding of link failures, I propose network modifications that attenuate or completely suppress the impact of link failures in parts of the network and thereby significantly reduce the risk of cascading failures. In a next step, I compare the topological characteristics of different kinds of supply networks to analyse how the trade-off between efficiency and resilience determines the structure of optimal supply networks. Finally, I examine what shapes the risk of incurring large scale cascading failures in a realistic power system model to assess the effects of the energy transition in Europe.

Item Type:	Thesis (PhD thesis)
Translated abstract:	Abstract Language UNSPECIFIED German
Creators:	Creators Email ORCID ORCID Put Code Kaiser, Franz Nikolas UNSPECIFIED orcid.org/0000-0002-7089-2249 UNSPECIFIED
URN:	urn:nbn:de:hbz:38-545820
Date:	9 January 2022
Language:	English
Faculty:	Faculty of Mathematics and Natural Sciences
Divisions:	Faculty of Mathematics and Natural Sciences > Department of Physics > Institute for Theoretical Physics
Subjects:	Natural sciences and mathematics Mathematics Physics
Uncontrolled Keywords:	Keywords Language power transmission grids English complex networks English graph theory English
Date of oral exam:	15 September 2021
Referee:	Name Academic Title Witthaut, Dirk JProf. Dr. Gross, David Prof. Dr. Zwart, Bert Prof. Dr. Maier, Berenike Prof. Dr.
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/54582