Seismic resilience evaluation and retrofitting strategy for substation system

Abstract

Electrical substation systems have always had an obvious vulnerability during earthquakes. To find an efficient retrofitting strategy at a substation’s functional network level, this paper proposes a seismic resilience evaluation framework that combines seismic simulation and function recovery. According to the structural connectivity and redundancy of substation seismic behavior, a directed acyclic graph was built. After careful consideration of the load transmission capacity of substation equipment and important coefficients of the output terminal, a structural and electrical dual-function network model was established using the Simulink module. The model was divided into four analytical steps for hierarchical simulation. Post-earthquake iterative analysis was carried out according to equipment repair efficiency. The post-earthquake repair sequence was found, and the steps to functional recovery were obtained. To quantify the seismic retrofitting efficiency of equipment, a set of seismic analytical methods for retrofitting was developed using a typical 220 kV substation. Seismic resilience analysis using the Monte Carlo method led to new optimal retrofitting strategies under different resource limitation conditions. These new strategies are presented in this paper.