Cascades in interdependent flow networks

TL;DR

This paper analyzes how interconnected energy distribution networks experience abrupt failures due to overloads, revealing that increased coupling can both enhance safety and raise systemic failure risks.

Contribution

It extends an analytical model of cascading failures to interdependent networks, demonstrating the dual effects of coupling on system stability.

Findings

Long-range flows cause first-order transition behavior.

Increased coupling expands safe operation regions.

Higher coupling also raises systemic failure risk.

Abstract

We investigate the abrupt breakdown behavior of coupled distribution grids under load growth. This scenario mimics the ever-increasing customer demand and the foreseen introduction of energy hubs interconnecting the different energy vectors. We extend an analytical model of cascading behavior due to line overloads to the case of interdependent networks and find evidence of first order transitions due to the long-range nature of the flows. Our results indicate that the foreseen increase in the couplings between the grids has two competing effects: on the one hand, it increases the safety region where grids can operate without withstanding systemic failures; on the other hand, it increases the possibility of a joint systems' failure.