Network Topology Optimization for Hybrid AC Power Grid Based on Critical Node Identification and Busbar Switching

The relentless construction and evolution of hybrid AC/DC power grids contribute to the rapid expansion of the regional transmission grid. The network structure is becoming more and more complex, which make power grids more prone to cascading failures. At the same time, there are individual critical nodes in the grid that have important impacts on the secure operation of hybrid AC power grid. Consequently, this study introduces a methodology aimed at optimizing the grid structure of hybrid AC-DC power grids, leveraging critical node identification and busbar switching. Initially, two performance indices are proposed, each addressing transient stability and multi-infeed short-circuit ratio, to assess the significance of individual buses within the hybrid AC-DC power grid. Following this, a bus-bar splitting-based countermeasure is suggested for optimizing the network structure. Subsequently, a case study conducted on a practical power grid is presented, wherein numerical results demonstrate that the proposed approach significantly enhances the security of hybrid AC/DC power grids.