Study On Power System Stability And Power System Stabilizer Control Based On Normal Form Theory

With the development of electric power system, power system has become an interconnected large-scale system. Interconnected network not only ensured the rational use of resources, but also improved the reliability of power system. However, the interconnected network also makes the problem of stability of power system becoming more and more serious, especially under the stress condition, some new problems and phenomena keep appearing. Because the traditional power system stability analysis method has its own shortcomings which can not give explanation to some new phenomena and new problems. So it is necessary to use new theory and method to research these new and dynamic phenomena.Since power system is a high-dimensional and complex nonlinear system, under the conditions of high-speed and heavy, the behavior of nonlinear plays an increasingly important role in modern power systems. Traditional linear analysis method regards power system as a linear system which neglected its nonlinear properties. Under some certain operating condition, especially in the stress operating conditions, adopting linear method will bring great errors and can not give reasonable interpretation to some dynamic phenomena even under a small disturbance. In this thesis, the author using normal form theory and method to research dynamic behavior under the stress power system. The normal form analysis method takes account of the nonlinear interaction, and it can reveals the new dynamic model that the linear analysis method can not reveals. This thesis researches the normal form theory and method, and deduces a second-order approximately analytic solution. The most important, it makes a further exploration and improvement on the key parameters (normal form transform parameters and the initial value of the normal form) through the normal form transformation. Then it measure and evaluate the index about nonlinear properties of power system dynamic model and the strength of nonlinear interaction. The author uses the normal form analysis method to analyze the power dynamic stability under the stress power system and draws some valuable conclusions.In this thesis, the author uses the normal form to solve the configuration problem of the power system stabilizer. Nonlinear participation factor and the index of nonlinear correlation play an important role in determining the configuration of the PSS. At last, the author compares with the traditional linear participation factors to get the configuration method of power system stabilizer under the stress power system.