Electrical loss minimization technique for wind generators based on a comprehensive dynamic modelling of induction machines

This paper proposes a novel model-based electrical losses minimization technique (ELMT), whose main original contribution lies in the overall power losses function which has been derived from a comprehensive dynamic space-vector model of the IM including the iron losses, expressed in the rotor flux oriented reference frame. Such a losses formulation, obtained from the IM input-output power balance, reveals more general and accurate than the others in literature and consequently the expression of the optimal efficiency reference flux to be given to the FOC control system is more general and accurate too. The proposed ELMT has been integrated in an IM-based wind generation system including a previously developed GNG-based MPPT. Results show that the new formulation of the overall power losses of the IM permits an increase of the IM efficiency up to 4% with respect to the classic loss equation proposed in scientific literature. The integration of the proposed ELMT in a real wind generation system leads to an increase of the active power injected into the power grid ranging from 33% at high wind speeds up to 200% at low wind speeds.