Urban Power Grid Resilience Assessment Method Considering Urban Lifeline Function

The occurrence probability of extreme disasters such as earthquakes is very low, but when they do occur, they pose significant risks to the stable and reliable operation of power systems. During the Wenchuan Earthquake in China on May 12, 2008, with a magnitude of 8.0, the power grid experienced a load loss exceeding 4 million kW, leaving at least 2.46 million users without electricity, resulting in enormous economic losses and severe social impacts. As a crucial energy provider in urban systems, the power grid plays a key supporting role in the operation of urban lifeline systems. Therefore, resilience assessment of urban power grids should not be limited to power restoration but should comprehensively consider the recovery of functional demands across urban lifeline systems. This study establishes a coupled system of water, electricity, and gas networks as urban lifelines and proposes urban power grid resilience assessment metrics based on the functional demands of urban lifeline systems. These metrics take into account the needs of different types of users for water, electricity, and gas resources under conditions where main grid power supply is constrained by earthquake disasters, focusing on voltage levels ranging from 10 kV to 220 kV.