Probabilistic Analysis Of Power System Small Signal Stability Based On Eigenvalue Method

With the enlargement of power system and the adoption of wind energy, the electrical system is becoming then more and more stochastic and complicated, and lots of content is used in the small signal stability. Many uncertain factors exists in the real power system, thus the probabilistic small signal stability has been concerned by researchers. This paper constructs the mathematic model of small signal stability with wind farm, developing the state equations. Then formulate the method of matrix of characteristic root sensibility, directing to two uncertain factors, finding out the probability density functions of the key characteristic root from sensibility, combining the Tetrachoric series and Hermite polymerization to get the probability of the stability. This paper uses the IEEE 39 bus system as an example to demonstrate the availability of the method.