Modeling and simulation of a soft-starter for large wind turbine induction generators

In this paper a soft-starter model and its control strategy for connecting solutions to the grid of different operation modes for a wind turbine generator of 2/0.5 MW are evaluated. The thyristors switching for different functions of the firing angle are discussed. A complete simulation model of a constant speed wind turbine with cage rotor and double stator windings induction generator is also presented. The system model proposed in this paper is developed in the dedicated power system simulation tool DIgSILENT, which gives access to an extensive library, but requires implementation of the relevant wind turbine model. The model can be used to study alternative control strategies for wind turbines and additional equipments such as soft-starter, compensation units and storage systems.