Research on Measures to Limit Short-Circuit Current by Changing the Structure of the Power Grid

This paper addresses the increasingly severe issue of excessive short-circuit currents brought about by the rapid development of large power grids. The working principles of structural changes in the grid as a means of limiting currents are studied, and an impedance matrix is constructed using the additional branch method to analyze the control effects of these limiting measures on short-circuit currents. To explore how to control the level of short-circuit currents in large power grids, this paper provides a detailed analysis of the working principles, advantages, and disadvantages of eight grid structural change measures, including electromagnetic ring network breaking, bus splitting, line interruption, and line coupling. The applicable conditions for each short-circuit-current-limiting measure are established, and specific engineering simulation cases are used to verify their effectiveness in limiting short-circuit currents. The results indicate that this research plays a significant role in controlling short-circuit currents in power systems, maintaining the safe and stable operation of power systems, and improving the structure of power system networks.