Stochastic Stability Analysis Of Power System With Random Small Excitation

With renewable energies increasingly integrated into power systems,there is increasing interest in stochastic analysis of power systems.Renewable energies has bright prospects because of its cleanness,pollution-free and renewable characteristics.However,because of its strong volatility and randomness,the power system has brought more random factors to influence the security of the power grid.So the research of stochastic stability analysis of power system as well as exploring its impact on the power system mechanism has important significance for guiding engineering practice.In this thesis,to analyze the stochastic foactos that affacts the stability of power system,research on the power system stability and related dynamic analysis are condcuted based on the stochastic model of stochastic differential equations by adding random factors to characterize the system.The main work of this thesis is as follows:1.According to the background of power system engineering,the mechanism of stochastic disturbance is analyzed,and the modeling process of power system stochastic model is systematically combed,and the simplification method of multi machine system is systematically discussed.2.On the basis of probability density satisfying FPK equations derived from stochastic model of the power system,the stational response of power system under the excitation of is researched with the random excitation of varied intensity.3.This paper use continuous time Markov chain theory to model the intensity evolution process of stochastic excitation,and add the system model to get the stochastic model of power system under the strength jump stochastic excitation.Accordingly.we get the corresponding FPK equation.The problem of stable response of the system under the random excitation of intensity jump is studied by the solution of the FPK equation.4.For the general formulation of first passage problem,This paper establish the first passage reliability function of the power system and its Kolmogorov equation.and study the reliability and the probability of the first passage time.