Voltage stability analysis and monitoring based on short circuit capacity

Application of the short circuit capacity (SCC) for voltage stability analysis and monitoring is proposed in this paper. By analyzing the SCC supplied from grid side and the critical SCC needed by the load side, the voltage stability status of power system can be quantitatively assessed. Therefore, a SCC-based voltage stability index and load margin are utilized to perform the voltage stability monitoring (VSM) task. For online tracing the SCC, a multi-source equivalent model is presented which avoids the impractical assumptions or approximations of system states. Finally, a VSM scheme is carried out for a practical power system in China and the result verifies the effectiveness of the proposed approach.