A New Method for Online Assessment of Voltage Stability

Abstract

In this paper we proposed a new technique for identifying system stress due to the loading in wide area of power system based on the phasor angle difference behavior. The difference of voltage phasor angle between busses can be transferred in to a simple conversion and trigonometric wave signal during load increasing. Using Discrete Fourier Transform (DFT), the signal will be transformed into the spectral frequency. The proposed technique will analyzed current condition by visualized the level of stress and proximity to voltage stability limit in the system based on the change of spectral frequency . This method also can be used to monitor such loss of generators or transmission line outages. The result shown that the proposed technique is simple, fast and reliable, requiring minimum data measurement and be suitable for Wide Area Monitoring System.