Analysis Of Power System Stability And Study Of Its Control Based On Modal Series Method

In 21 century, the tendency of our power industry will be "Transmission electric power from West to East, exchange power between South and North, interconnection in the whole country." Because of this large-scale interconnected power networks which are operating closely at a limited transmission level and all kinds of fast controllers which are called on to improve systems' dynamic behavior, such as fast exciters, HVDC, FACTS and so on, the modern power system is inherently a nonlinear system, called as a stressed power system. The most notable characteristic of the kind of system is that there is intense nonlinear interaction among generators, so, although the system is only subjected to small disturbance, it will exhibit intense nonlinear characteristic, and the oscillation modal interactions become the main reason of affecting the dynamic characteristic and stability of system.To the stressed power systems that are mentioned above, the analysis methods based on linearization theory have difficult to explain the substance of some nonlinear singularity phenomenon, because it is not easy to consider the inertial nonlinear dynamic structural information of power system by using these linear analysis methods. So, nowadays, at home and overseas, the Normal Forms of vector fields has been widely applied to study the dynamic characteristic of nonlinear power system. It successfully extends the linear system theory concepts to facilitate the analysis of nonlinear systems. However, this method have some drawback when it is applied to analyze power systems, for example, it needs state variables that do not...