A new method for analyzing the probability of voltage and frequency stability status based on Markov Chain

摘要

The prediction of power system stability status is one of the major concerns among designers to maintain the performance in an acceptable range. So, providing indices that investigate every stability aspect seems to be essential. On the other hand, there is a relationship between Voltage and Frequency Stability (VFS) since any changing of stability status, in each one leads to the changes in another. Therefore, introducing a method that can analyze both aspects of stability is essential. In this paper, an index is proposed to analyze the VFS, either separately or together. In this regard, the relation between these two classes of stability is brought forward as Markov Stochastic Chain. Then, a stochastic index is introduced for VFS analysis. The proposed index is a combination of the online measurement matrix of the voltage and the frequency of the weak bus and event probability matrix of voltage and frequency. Also, the index has an acceptable speed and accuracy. To demonstrate the efficiency of the proposed method, some simulations have been carried out on the IEEE 39bus, which shows the speed and accuracy of the offered index in comparison to the similar methods.