Modeling and control of doubly fed induction generator wind turbines by using Causal Ordering Graph during voltage dips

Nowadays, the most widely used variable speed wind turbine type for units above 1 MW is doubly fed induction generator (DFIG). As the wind power penetration continues to increase, wind turbines are required to remain connected during grid faults to ride-through the faults. This paper gives a control oriented modeling of DFIG wind turbines by using causal ordering graph (COG). The control system consists of the maximum power point tracking (MPPT), the control of the reactive power and the power quality, and the control of the intermediate DC bus. Simulation results show that the proposed modeling and control strategy can provide adequate control of the DFIG wind turbine system during voltage dips.