Research on optimal allocation of energy storage in urban power grids considering static voltage stability

Abstract

As new energy sources scale up for integration into urban power grids， there is a growing spatiotemporal mismatch between supply and demand in power systems. This mismatch could gradually undermine the static voltage stability of the power systems， jeopardizing electrical safety. To counter this challenge， a novel method for the optimal allocation of energy storage in urban power grids is proposed， with a special focus on maintaining static voltage stability under a mismatch of supply and demand. The method begins with a characteristic analysis of the mismatch between supply and demand in urban power grids. Assessment indicators for the mismatch in space and time are established. Following this， the number of power flow solutions is analyzed using the discriminant of a quadratic equation based on power flow equations of transmission lines， leading to the introduction of an index for assessing the static voltage stability of urban power grids. Subsequently， an optimal allocation model for energy storage devices is developed by weighting the aforementioned indicators of the spatiotemporal mismatch as well as static voltage stability. Lastly， the effectiveness and superiority of the proposed method are verified through simulation.

Keywords

• spatiotemporal mismatch between supply and demand
• static voltage stability
• new-type urban power grid
• optimal allocation of energy storage