A multi-source power grid's resilience enhancement strategy based on subnet division and power dispatch

Abstract

A resilience enhancement strategy based on subnetting is proposed to improve the robustness and repair ability of multi-source power grids. Firstly, based on the characteristics of renewable energy and the principle of cascading failure, the network is divided into multiple stable and sustainable subnets by using the power flow data and island operation conditions in the system, and the key nodes in the subnet are identified by the index of interval electrical betweenness. Considering the three stages of the resilience cycle, the nodes that should be protected or repaired are determined at each time scale, and four different attack and repair strategies are established on this basis. To verify the effectiveness of the proposed method, the robustness and resilience of power networks with and without renewable energy are evaluated from different perspectives, and the impact of this method on improving network resilience is quantitatively evaluated. Finally, the improved IEEE 118-bus system is simulated. The results show that the attack and repair strategies based on subnetting have significant effects on both multi-source power grids and traditional power grids. The resilience enhancement method proposed in this paper can identify grid weaknesses and formulate repair measures that can provide support for improving the defense and resilience of the power grid.