An integrated method for transient security assessment of power systems

A new technique of determining the first swing stability limit of power systems by combining the equal area criterion (EEAC) method, the roots evaluation method and a fast numerical integration method is presented. The proposed method consists of two phases: prediction and correction. In the first phase, the EEAC method is adopted for critical clearing time (CCT) estimation considering that the EEAC method is extremely fast. In the second, the fast numerical integration method and roots evaluation method are combined and used for CCT correction. The method has been tested and practically implemented.<>