Application of a modal-based transient energy function to a large-scale stressed power system: Assessment of transient stability and transient voltage dip

In this paper a modal-based transient energy function (MTEF) is used to analyse a large-scale stressed power system exhibiting the inter-area mode phenomenon. The analysis consists of two parts. In the first part, direct transient stability analysis of the inter-area mode is conducted by determining the dominant modes of oscillation involved in the non-linear interaction. Using the machines that have large participation in these modes, relevant disturbed machine groupings are formed. These groupings are then used in the MTEF method for transient stability assessment. In the second part, the MTEF is also used to predict the post-disturbance voltage dip at various buses using an energy based criteria. The developed procedures are tested on a 161-generator coherency-based dynamic equivalent of the Northern States Power system which is part of the Mid-continent Area Power Pool in North America.