Distance to voltage collapse through second-order eigenvalue sensitivity technique

In this paper, the voltage collapse phenomenon is discussed and a method that determines the distance to voltage collapse is proposed by using second-order eigenvalue sensitivity technique. Sensitivities to changes in load bus voltage and the level of voltage that is most sensitive to load changes can be determined by this method. The technique will also permit the determination of a minimum voltage level that can be estimated to track the status of the system as to how close and where the voltage collapse might occur. It will give not only the estimated distance, but also changes in the other state variables such as the load angle, the mth generator rotor angle and the system frequency.