Approach to identify the critical cluster of machines based on line transient potential energy and voltage

Abstract

Reliability and computational simplicity in identification of cluster of critical machines are of primary importance in application of direct and hybrid transient stability assessment methods such as TEF,EEAC and hybrid TEF and hybrid EEAC.In the paper,a new approach is proposed for classifying machines into critical cluster and remaining cluster by identifying critical cutset(the weakest cutset)with quantitative assessment index,which is built on the basis of investigation in the feature of transient potential energy over network injected into the post-fault system and the change of bus voltage after removal of the disturbance.The algorithm only requires variables of line power,bus phase angle and bus voltage along the post-fault trajectory instead of generator dynamic variables.The case studies on the10machines39buses New England system are given to show the validation of this method.