Computation of critical clearing time using an integrated approach

A fast computation technique of critical clearing time (CCT) has been proposed using an integrated approach. The technique combines the advantage of energy function based analysis and the time domain stability analysis method for calculating the CCT useful for removal of system contingency in a power network. This integrated approach computes the approximate CCT first using the energy function approach and uses the approximate CCT as the starting to the time domain analysis method which gives a tuned CCT. The proposed integrated approach estimates CCT very fast compared to the normal time domain approach. This method has been tested on WSCC 9bus system and New England 39 bus Test System.