Improving the efficiency of a Doubly-Fed Induction Generator in variable speed wind turbines under different modes of operation considering core loss

Design and Implementation of Predictive Controllers on the Rectifier and Quasi Impedancesource Inverter in a Wind Energy Conversion System Based on Permanent Magnet Synchronous Generator

“…2, respectively. In the wind power generation systems, generators can be classified into four primary types: I) fixed-speed squirrel-cage induction generator [5,6], II) variable-speed wound rotor induction generator [7] that applies variable rotor resistance, III) variable-speed doubly fed induction generator (DFIG) [8,9] that applies a frequency converter between the grid and its rotor windings and IV) variable-speed synchronous generator [10], which is either a wound rotor synchronous generator or a permanentmagnet synchronous generator (PMSG). Depending on the specific structure is used, the term of power converter in the two figures includes different types of power electronics components such as a soft starter (a), an external-variable resistor for the rotor (c), a rectifier connected to the stator (e) and or connected to the rotor (f, g, h) and or a frequency converter (b, d, e, g, h).…”