Transient stability limit conditions analysis using a corrected transient energy function approach

This paper addresses the issue in developing tools for transient stability limit conditions analysis in on-line power system operation. Concepts, including corrected potential energy and corrected potential energy boundary surface, are proposed for improving use of hybrid method in transient stability limit conditions analysis. It is shown that the value of corrected transient energy function (CTEF), which is the sum of corrected kinetic energy and corrected potential energy is of conservation (maintains constant value) during post-fault transient period. Efficient criteria in identifying first swing stability behavior are also developed and used in the approach incorporating CTEF analysis in a hybrid method to evaluate corrected hybrid transient energy margin. Initial simulation results on the 10-machine New England and on the 50-generator IEEE test power systems show that the approach is promising in evaluations of transient stability limit conditions of power systems both for plant and inter-area mode disturbances.