Modal Analysis of Power Systems with Doubly Fed Induction Generators

Abstract: To ensure the reliable operation of the power system, stability analysis considering the interaction between wind power and power system must be understood. In this thesis, the impact of wind power on the stability of Nordic32A power system is of interest. Many wind farms nowadays employ doubly fed induction generator (DFIG) variable speed wind turbines. In this thesis, a third order DFIG model and its control circuits are employed. The particle swarm optimization algorithm is developed to tune the power system stabilizer, which can greatly increase the computational efficiency and improve the damping of the power system. Modal analysis is conducted to investigate the behavior of a wind power plant in a conventional power system. The interaction between generators is investigated when we add wind power plants in different locations. In some cases, some unstable oscillation modes may be observed due to the inter-area and local oscillations among different synchronous generator groups in the system.